The sources, in the open
Every source, graded
Every source this book rests on, the exact claim it carries, the grade I gave it where it takes one, the pages it is used on, and its full citation with a DOI or PMID: 170 lines and 169 sources, counting each register entry as one source (one paper carries two claims); a guidance entry can bundle several documents from one issuer, each linked in its full citation. Open the line to see the book’s own sentences that rest on the paper, and the instruction the reader is given beside them. Nothing here is behind a login.
If you are a reader. The grades are mine and the rubric is on the home page and on page 10 of the book: they rate each source rather than a body of evidence, so a Moderate says how good the study is and nothing about whether the idea is right. A claim marked Emerging is not yet shown properly in humans, which is not the same as shown not to work.
If your paper is here. One line, two minutes. The question is not whether the
evidence is good, which you already know. It is whether I have used your work for something it
does not support. Open What the book does with it on your line: it shows the sentences that rest on your paper and, where the page gives one, the instruction beside them. Every line has its own address, so you can link to yours in a reply. Write to [email protected] with the line and what is wrong with it. Where you are right, the page and the next printing change, and the change goes on the corrections page.
The system: how the pillars connect · Sleep · Eat · Across sexes and life stages · Exercise & recovery · Data and support · Guidance and formularies · Habits, and everything else · The studies behind what I left out
Full citations, and how they were checked. Under every source is its full citation with a DOI or PMID wherever one is issued, taken from the PubMed record on 4 September 2026 and matched to the entry by author, journal, year and the study the entry describes. Where a paper appeared online the year before its printed issue, the printed year is shown and the line says so. Guidance documents, labels and fact sheets link to the issuing body’s own page. Where an entry bundles several documents and one of them is not named specifically, that part is not linked and the line says so. If your record is wrong, that is a correction I want.
Where my interest lies. I am not a doctor and I am not a researcher. I am in the wellness industry, and you should not have to take my word for what that means: my work there includes sleep supplements, and overlaps directly with the supplement pages in this book. The book recommends no product, brand, or company. Where a real name appears, it is a source being cited or a method being compared, and a medicine’s label is sometimes the only source there is. The support chapter opens by trying to talk you out of most of what is in it. The evidence was checked as of August 2026, every dose and threshold against the document it names. Read the grades on this page knowing that.
The system: how the pillars connect
| The source | What the book says it shows, and where |
|---|---|
| Koemel et al., eClinicalMedicine 2026 (UK Biobank, n=59,078).Moderate | Small gains across all three tracked with longer life. Between the least and most favorable sleep, activity and diet tertiles the estimated gap was 9.35 years of life, the decade figure on the critical-path page.Used on page 12 Full citationKoemel et al. Minimum combined sleep, physical activity, and nutrition variations associated with lifeSPAN and healthSPAN improvements: a population cohort study. EClinicalMedicine. 2026;92:103741. doi:10.1016/j.eclinm.2025.103741 · PMID 41768982 What the book does with itp12“In the UK Biobank analysis behind that line, the gap between the best and worst sleep, diet and activity combinations came to almost a decade of life (Koemel 2026).” And on page 12 the reader is told · In shortRead the figure as the size of the association around basic habits, and how stacking them tracks with a meaningful difference |
| 1 · Nutrients → Fitness. Morton et al., BJSM 2018 (49 RCTs, n≈1,900).Strong | Protein augments resistance-training gains. Full entry under Eat.Used on pages 10, 29, 32, 42, 46 Full citationMorton et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018;52:376-384. doi:10.1136/bjsports-2017-097608 · PMID 28698222 Published online the year before its printed issue; the printed year is shown. What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p32“The gains at any dose are modest, and they came with training attached, which is the only way the pooled trials tested it (Morton 2018).” p32“That band comes from the older-adult and training literature (Bauer 2013; Phillips 2016; Morton 2018), and no women-specific trial sets it.” And on page 32 the reader is told · Remember thisAim at these numbers; going past the protein figure buys little. Test for a micronutrient only when your diet, symptoms or medicines give a reason to p42“Protein supplies the material (Morton 2018), recovery banks it (Saner 2020), and the training itself raises slow-wave sleep (Kredlow 2015).” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can |
| 2 · Sleep → Recovery. Van Cauter, Leproult & Plat, JAMA 2000.Emerging | The overnight growth hormone pulse tracks slow-wave sleep, in a correlational study in men. A correlation cannot show the pulse needs this stage, which is why the map names sleep as a whole and draws the link dashed.Used on pages 23, 24, 45 Full citationVan Cauter, Leproult & Plat. Age-related changes in slow wave sleep and REM sleep and relationship with growth hormone and cortisol levels in healthy men. JAMA. 2000;284:861-8. doi:10.1001/jama.284.7.861 · PMID 10938176 What the book does with itp23“When researchers sampled blood through the night, most of the growth hormone released came during the deep sleep of the first cycles (Van Cauter 2000, measured in men).” p23“The overnight growth-hormone pulse coincides with the deep sleep of the first cycles, in the same Van Cauter study.” And on page 23 the reader is told · Remember thisTraining buys minutes of deep sleep, and a nightcap costs you the rest of the night p45“Its biggest pulse comes in the first cycles of the night, alongside the deep sleep there (Van Cauter 2000, correlational and in men).” And on page 45 the reader is told · Remember thisFive nights at four hours cut the muscle-building signal by about 19%, though an exercise arm in the same study held it normal |
| 3 · Nutrients ↔ Gut. Wastyk et al., Cell 2021.Emerging | A two-arm feeding trial. The book uses the fermented arm for diversity and the fiber arm for enzyme capacity. The pre-specified immune endpoint was null; n≈18 per arm.Used on pages 35, 36 Full citationWastyk et al. Gut-microbiota-targeted diets modulate human immune status. Cell. 2021;184:4137-4153.e14. doi:10.1016/j.cell.2021.06.019 · PMID 34256014 What the book does with itp35“The fiber arm changed the gut’s enzyme capacity without changing diversity (Wastyk 2021).” And on page 35 the reader is told · Remember thisAdd fiber a few grams a week, with water (a convention) |
| 4 · Sleep → Nutrients. Tasali et al., JAMA Intern Med 2022 (RCT, n=80).Established | Extending sleep cut intake by ~270 kcal a day. The behavioral result holds. The accompanying ghrelin and leptin findings did not, and later pooled trials found no change in either, so the book takes nothing from them beyond that null.Used on page 32 Full citationTasali et al. Effect of Sleep Extension on Objectively Assessed Energy Intake Among Adults With Overweight in Real-life Settings: A Randomized Clinical Trial. JAMA Intern Med. 2022;182:365-374. doi:10.1001/jamainternmed.2021.8098 · PMID 35129580 What the book does with itp32“They ate about 270 fewer calories a day (Tasali 2022).” And on page 32 the reader is told · Remember thisAim at these numbers; going past the protein figure buys little. Test for a micronutrient only when your diet, symptoms or medicines give a reason to |
| 5 · The day’s practice → Stable·N2. Laventure et al., PLOS Biol 2016.Emerging | N2 spindles consolidate motor-skill learning. Spindle frequency mediated the link between group and gain, and amplitude and duration also shifted. A small lab experiment on finger-tapping, and nothing on fitness.Used on page 22 Full citationLaventure et al. NREM2 and Sleep Spindles Are Instrumental to the Consolidation of Motor Sequence Memories. PLoS Biol. 2016;14:e1002429. doi:10.1371/journal.pbio.1002429 · PMID 27032084 What the book does with itp22“Only the N2 group improved beyond the others by morning, and the change in spindle frequency during the replay mediated the gain (Laventure 2016).” And on page 22 the reader is told · In shortGive the night its full length, hold the wake time, and fix what wakes you at 2am. Getting up to pass urine most nights is worth a doctor’s look |
| 6 · Deep ↔ Stable·N2. Ng et al., eLife 2025.Emerging | Slow waves and sleep spindles couple through the night, at a small effect size, which is the map link between deep and stable sleep.Used on page 22 Full citationNg et al. Bayesian meta-analysis reveals the mechanistic role of slow oscillation-spindle coupling in sleep-dependent memory consolidation. Elife. 2025;13. doi:10.7554/eLife.101992 · PMID 41060323 What the book does with itp22Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 22 the reader is told · In shortGive the night its full length, hold the wake time, and fix what wakes you at 2am. Getting up to pass urine most nights is worth a doctor’s look |
| 7 · Fitness → Deep sleep. Kredlow et al., J Behav Med 2015 (meta).Established | Exercise increases slow-wave sleep. Confidence is good; the gain is single-digit minutes, and the abstract reports moderation by sex, age and baseline activity rather than by sleep quality.Used on pages 23, 24, 42 Full citationKredlow et al. The effects of physical activity on sleep: a meta-analytic review. J Behav Med. 2015;38:427-49. doi:10.1007/s10865-015-9617-6 · PMID 25596964 What the book does with itp23“On the input side, pooled trials find exercise nudges slow-wave sleep upward, at a small effect size that converts to a handful of minutes (Kredlow 2015).” And on page 23 the reader is told · Remember thisTraining buys minutes of deep sleep, and a nightcap costs you the rest of the night p42“Protein supplies the material (Morton 2018), recovery banks it (Saner 2020), and the training itself raises slow-wave sleep (Kredlow 2015).” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can |
| 8 · Nutrients → Deep sleep. St-Onge et al., JCSM 2016.Emerging | Fiber predicted more slow-wave sleep, in one small crossover.Used on page 29 Full citationSt-Onge et al. Fiber and Saturated Fat Are Associated with Sleep Arousals and Slow Wave Sleep. J Clin Sleep Med. 2016;12:19-24. doi:10.5664/jcsm.5384 · PMID 26156950 What the book does with itp29Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| 9 · Sleep ↔ Gut. Smith et al., PLOS One 2019.Emerging | Sleep tracks with microbiome diversity (cross-sectional).Used on pages 35, 36 Full citationSmith et al. Gut microbiome diversity is associated with sleep physiology in humans. PLoS One. 2019;14:e0222394. doi:10.1371/journal.pone.0222394 · PMID 31589627 What the book does with itp35“Where a direction is clear it tends to run from lifestyle into the gut (Smith 2019; Allen 2018, n=32, six weeks, reversing on detraining).” And on page 35 the reader is told · Remember thisAdd fiber a few grams a week, with water (a convention) |
| 10 · Fitness ↔ Gut. Allen et al., MSSE 2018.Emerging | Bacteria associated with fiber breakdown increased with exercise in 32 humans over six weeks, reversing on detraining; short-chain fatty acids rose in lean participants only, and how exercise raises them is not settled. The arrow has not been run the other way, from the gut to strength, in anything I read.Used on pages 35, 36 Full citationAllen et al. Exercise Alters Gut Microbiota Composition and Function in Lean and Obese Humans. Med Sci Sports Exerc. 2018;50:747-757. doi:10.1249/MSS.0000000000001495 · PMID 29166320 What the book does with itp35“Where a direction is clear it tends to run from lifestyle into the gut (Smith 2019; Allen 2018, n=32, six weeks, reversing on detraining).” And on page 35 the reader is told · Remember thisAdd fiber a few grams a week, with water (a convention) |
| 11 · Stable·N2 → Nutrients. Vallat et al., Cell Rep Med 2023 (n>600, replicated in >1,900).Emerging | Spindle coupling predicts next-day fasting glucose. Observational, on a surrogate outcome. No human trial has manipulated spindles to test it, so it is graded below the size of the cohort.Used on page 22 Full citationVallat et al. Coordinated human sleeping brainwaves map peripheral body glucose homeostasis. Cell Rep Med. 2023;4:101100. doi:10.1016/j.xcrm.2023.101100 · PMID 37421946 What the book does with itp22“In a separate analysis of thousands of nights, how tightly deep-sleep slow waves locked onto N2 spindles predicted next-day fasting glucose (Vallat 2023, observational).” And on page 22 the reader is told · In shortGive the night its full length, hold the wake time, and fix what wakes you at 2am. Getting up to pass urine most nights is worth a doctor’s look |
| 12 · REM back-loading. Carskadon & Dement, Principles and Practice of Sleep Medicine, 6th ed. 2017.Established | Sleep architecture: deep sleep front-loaded, REM building toward morning. A textbook chapter, and a direction no longer in dispute, which is the rubric’s second route to Established; the map draws the link solid on that basis. Park & Weber 2020 describes the same alternation, mostly in animals.Used on pages 17, 22, 24, 25, 26 Full citationCarskadon MA, Dement WC. Normal Human Sleep: An Overview. In: Kryger MH, Roth T, Dement WC, eds. Principles and Practice of Sleep Medicine, 6th ed. Philadelphia: Elsevier; 2017:15-24. doi:10.1016/B978-0-323-24288-2.00002-7 What the book does with itp25“Decades of laboratory sleep recording established how the stages are distributed through the night: REM is scarce early, builds cycle by cycle, and in a typical night dominates the last two hours before waking (Carskadon & Dement 2017, textbook chapter).” And on page 25 the reader is told · Remember thisCutting the morning short mostly costs REM. Nothing sold is shown to put it back, in the trials I found |
| Ohayon et al., Sleep 2004 (meta, 65 studies, n=3,577).Established | Normative stage percentages across the lifespan: deep sleep 10 to 20% of the night and falling with age, REM 20 to 25%. Settled sleep-lab measurement of how much of a night each stage occupies, which is what the book cites it for.Used on page 17 Full citationOhayon et al. Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals: developing normative sleep values across the human lifespan. Sleep. 2004;27:1255-73. doi:10.1093/sleep/27.7.1255 · PMID 15586779 What the book does with itp17Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
Sleep
| The source | What the book says it shows, and where |
|---|---|
| Abernethy & Todd, Eur J Clin Pharmacol 1985.Emerging | Low-dose combined pills lengthen caffeine half-life from about 5.4 to 7.9 hours by blocking the enzyme that clears it. A small pharmacokinetic study, graded accordingly.Used on page 26 Full citationAbernethy & Todd. Impairment of caffeine clearance by chronic use of low-dose oestrogen-containing oral contraceptives. Eur J Clin Pharmacol. 1985;28:425-8. doi:10.1007/BF00544361 · PMID 4029248 What the book does with itp26“On the combined pill, caffeine took about half again as long to clear in one small older study (Abernethy & Todd 1985), so a longer gap is the starting point; no trial has set the number.” |
| Hilli et al., J Clin Pharmacol 2008 (n=29).Emerging | The combined pill raises melatonin exposure four- to five-fold by the same route.Used on page 18 Full citationHilli et al. The effect of oral contraceptives on the pharmacokinetics of melatonin in healthy subjects with CYP1A2 g.-163C>A polymorphism. J Clin Pharmacol. 2008;48:986-94. doi:10.1177/0091270008318669 · PMID 18490497 What the book does with itp18Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Scheer et al., PNAS 2009 (n=10).Emerging | With the body clock deliberately pushed out of step with the day, glucose, appetite hormones, and blood pressure all worsened. Ten participants, under laboratory conditions, and the reason misalignment is treated separately from short sleep.Used on page 62 Full citationScheer et al. Adverse metabolic and cardiovascular consequences of circadian misalignment. Proc Natl Acad Sci U S A. 2009;106:4453-8. doi:10.1073/pnas.0808180106 · PMID 19255424 What the book does with itp62Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 62 the reader is told · The move on that pageExercise Daylight at the right end of the day anchors the clock, and a walk is the easy way to get it. On a shift, bright light and some movement early hold alertness; wind down before the daytime block. On the flight, get up and move every couple of hours. If a calf swells or aches in the days after, that is a same-day question; with breathlessness, chest pain or coughing blood alongside it, an emergency call. Both are on page 72. |
| Leary et al., JAMA Neurol 2020 (MrOS n=2,675; WSC n=1,386).Moderate | Each 5 points less REM share was associated with ~13% higher all-cause mortality, replicated. Observational, one night of recording; illness, antidepressants and apnea also lower REM, which the analysis evaluated, and the association held.Used on pages 25, 26 Full citationLeary et al. Association of Rapid Eye Movement Sleep With Mortality in Middle-aged and Older Adults. JAMA Neurol. 2020;77:1241-1251. doi:10.1001/jamaneurol.2020.2108 · PMID 32628261 What the book does with itp25“The finding replicated in a younger mixed cohort of 1,386 followed for two decades (Leary 2020).” And on page 25 the reader is told · Remember thisCutting the morning short mostly costs REM. Nothing sold is shown to put it back, in the trials I found |
| van der Helm et al., Curr Biol 2011 (n=18 with sleep recording).Emerging | Low prefrontal gamma during REM, rather than REM duration, tracked with an overnight drop in amygdala response. Small, single lab, and descriptive only.Used on pages 25, 26 Full citationvan der Helm et al. REM sleep depotentiates amygdala activity to previous emotional experiences. Curr Biol. 2011;21:2029-32. doi:10.1016/j.cub.2011.10.052 · PMID 22119526 What the book does with itp25“Those with the lowest prefrontal gamma activity during REM, a proxy for adrenergic tone, showed the largest overnight drop in amygdala response to the previous day (van der Helm 2011).” And on page 25 the reader is told · Remember thisCutting the morning short mostly costs REM. Nothing sold is shown to put it back, in the trials I found |
| Rudoy et al., Science 2009 (laboratory experiment).Emerging | Sounds cued during sleep sharpened recall of exactly the cued locations on waking. One small lab study on spatial memory, in young adults.Used on page 22 Full citationRudoy et al. Strengthening individual memories by reactivating them during sleep. Science. 2009;326:1079. doi:10.1126/science.1179013 · PMID 19965421 What the book does with itp22“An earlier experiment also cued learned items with sounds during deep sleep and sharpened exactly the cued memories on waking (Rudoy 2009).” And on page 22 the reader is told · In shortGive the night its full length, hold the wake time, and fix what wakes you at 2am. Getting up to pass urine most nights is worth a doctor’s look |
| Park & Weber, Front Psychol 2020 (review). Also cited under link 12.Emerging | Deep sleep and REM alternate through the night. Descriptive, and mostly rodent-derived.Used on pages 25, 26 Full citationPark & Weber. Neural and Homeostatic Regulation of REM Sleep. Front Psychol. 2020;11:1662. doi:10.3389/fpsyg.2020.01662 · PMID 32793050 What the book does with itp25“It typically follows the NREM sleep of the same cycle, which is deep early in the night and light by morning (Park & Weber 2020, a review).” And on page 25 the reader is told · Remember thisCutting the morning short mostly costs REM. Nothing sold is shown to put it back, in the trials I found |
| Buxton et al., Diabetes 2010 (inpatient, n=20 men).Emerging | A week of five-hour nights cut insulin sensitivity ~11% against the same men when sleep-replete, measured directly. No parallel control group, no recovery measurement, men only, and the authors say so.Used on pages 20, 48 Full citationBuxton et al. Sleep restriction for 1 week reduces insulin sensitivity in healthy men. Diabetes. 2010;59:2126-33. doi:10.2337/db09-0699 · PMID 20585000 What the book does with itp20“Buxton and colleagues measured that directly, though whether restoring the sleep restores the sensitivity was not tested there (Buxton 2010).” And on page 20 the reader is told · How to use itFix the sleep before you buy a glucose monitor. Do not expect the blood work to follow automatically, because the one sleep-extension trial did not find that p48“Short sleep and blood sugar move together, though the study behind it had no control arm (Buxton 2010) and a trial extending sleep did not move insulin sensitivity (Beals 2026).” And on page 48 the reader is told · Remember thisMost of these move with the three pillars. Lp(a) is inherited, and the guideline has it measured once in adulthood |
| Beals et al., Diabetes Care 2026 (RCT, n=29).Emerging | Six weeks of sleep extension did not improve insulin sensitivity. A small null on a surrogate endpoint.Used on pages 20, 48 Full citationBeals et al. Sleep Extension Improves Sleep Health but Not Insulin Sensitivity in People With Overweight or Obesity Who Maintain Habitual Short Sleep Schedules. Diabetes Care. 2026;49:740-745. doi:10.2337/dc25-2083 · PMID 41564347 What the book does with itp20“Their sleep improved, but measured insulin sensitivity did not (Beals 2026, n=29).” And on page 20 the reader is told · How to use itFix the sleep before you buy a glucose monitor. Do not expect the blood work to follow automatically, because the one sleep-extension trial did not find that p48“Short sleep and blood sugar move together, though the study behind it had no control arm (Buxton 2010) and a trial extending sleep did not move insulin sensitivity (Beals 2026).” And on page 48 the reader is told · Remember thisMost of these move with the three pillars. Lp(a) is inherited, and the guideline has it measured once in adulthood |
| Benjafield et al., Lancet Respir Med 2019.Emerging | Modeled global sleep apnea prevalence, ~936m aged 30 to 69. Modeled from a limited set of national studies. Nobody counted.Used on page 20 Full citationBenjafield et al. Estimation of the global prevalence and burden of obstructive sleep apnoea: a literature-based analysis. Lancet Respir Med. 2019;7:687-698. doi:10.1016/S2213-2600(19)30198-5 · PMID 31300334 What the book does with itp20“Benjafield and colleagues produced the first global figure by modeling from the national studies that existed: roughly 936 million adults aged 30 to 69 with mild-to-severe disease (Benjafield 2019).” p20“Benjafield 2019, a modeled global estimate built from a limited set of national studies.” And on page 20 the reader is told · How to use itGet assessed if either of the following applies: (1) loud snoring, gasping or stopped breathing at night, (2) waking unrefreshed however long you spend in bed |
| Kyle et al., Sleep 2014 (n=16, within-subject).Emerging | Sleep restriction therapy cut measured sleep by over an hour in the first weeks, with more daytime sleepiness and slower reaction times that had settled by three months. Small and uncontrolled; the basis for the caution on sleepiness.Used on page 21 Full citationKyle et al. Sleep restriction therapy for insomnia is associated with reduced objective total sleep time, increased daytime somnolence, and objectively impaired vigilance: implications for the clinical management of insomnia disorder. Sleep. 2014;37:229-37. doi:10.5665/sleep.3386 · PMID 24497651 What the book does with itp21“One core component, sleep restriction, makes most people sleepier for a few weeks before it helps (Kyle 2014).” And on page 21 the reader is told · The one to keepHold the wake time within about half an hour on the days the night was long enough (a convention). After a short night, the extra sleep comes first; it is the sleeping in without a deficit that drifts the clock |
| Angarita et al., Addict Sci Clin Pract 2016.Emerging | Cannabis lowers REM; quitting brings a vivid-dream rebound. A narrative review of lab and observational work, no pooled trials.Used on page 26 Full citationAngarita et al. Sleep abnormalities associated with alcohol, cannabis, cocaine, and opiate use: a comprehensive review. Addict Sci Clin Pract. 2016;11:9. doi:10.1186/s13722-016-0056-7 · PMID 27117064 What the book does with itp26Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Melatonin SmPCs: Circadin, and the immediate-release 3 mg products (Colonis, Orion), electronic Medicines Compendium.Guidance | By document. Circadin 2 mg SmPC (text revised January 2021): 4.5, estrogen (contraceptive or HRT), fluvoxamine and quinolones raise melatonin levels; 4.6, pregnancy and breastfeeding not recommended; 4.4, autoimmune disease; 4.2, hepatic impairment; 5.1, trialed at 55 and over. Colonis 3 mg SmPC (March 2025): 4.5, warfarin; 4.6, pregnancy and breastfeeding; 4.7, driving. Full citationelectronic Medicines Compendium (Flynn Pharma / RAD Neurim). Circadin 2 mg prolonged-release tablets - Summary of Product Characteristics. medicines.org.uk/emc/product/2809/smpc electronic Medicines Compendium (Colonis Pharma Ltd). Melatonin 3 mg film-coated tablets - Summary of Product Characteristics. medicines.org.uk/emc/product/10405/smpc electronic Medicines Compendium (Orion Corporation). Melatonin Orion 3 mg tablets - Summary of Product Characteristics. medicines.org.uk/emc/product/15792/smpc |
| CDC Yellow Book 2026, jet lag disorder.Guidance | Trip-specific timing for light, melatonin and caffeine. The book points readers here rather than printing a schedule, and the chapter is clinician guidance carrying no trial of its own.Used on page 62 Full citationCenters for Disease Control and Prevention (CDC). CDC Yellow Book 2026: Health Information for International Travel - Jet Lag Disorder (Riedy SM, Williams SG). cdc.gov/yellow-book/hcp/travel-air-sea/jet-lag-disorder.html What the book does with itp62“Sleep Flying: plan light and sleep by your route, the time zones crossed and your usual schedule, using the CDC Yellow Book’s jet lag chapter rather than a direction rule; for a very short stay, keeping your home schedule may beat adjusting.” And on page 62 the reader is told · The move on that pageSleep Flying: plan light and sleep by your route, the time zones crossed and your usual schedule, using the CDC Yellow Book’s jet lag chapter rather than a direction rule; for a very short stay, keeping your home schedule may beat adjusting. On nights: one consolidated block at the same time each working day, bedroom dark, cool and quiet, dark glasses for the daylight on the way home, never at the wheel. If you are fighting sleep at the wheel, stop driving: hand it over or pull somewhere safe (page 72). |
| Herxheimer & Petrie, Cochrane 2002 (10 RCTs).Established | Low doses at the destination bedtime reduced jet lag, most clearly flying east across five or more zones, with no further gain at higher doses. Ten small trials from 2002, which is why it sits a rung down.Used on pages 18, 62 Full citationHerxheimer & Petrie. Melatonin for the prevention and treatment of jet lag. Cochrane Database Syst Rev. 2002. doi:10.1002/14651858.CD001520 · PMID 12076414 What the book does with itp62“In some countries it is a prescription medicine, so whether and when to take it is a question for a pharmacist or a doctor (Herxheimer 2002; cautions on page 18).” And on page 62 the reader is told · The move on that pageEat Meal timing is its own clock cue. Flying, skip the airline meal served at your 2am and eat at the destination’s next real mealtime, unless medicines, diabetes, pregnancy or an eating disorder keep meals on a schedule. On nights, avoid a heavy meal in the biological night. Alcohol on the flight costs you the back half of the first night. Melatonin is the other lever. Jet lag is the stronger case, shift work the weaker one (Liira 2014). In some countries it is a prescription medicine, so whether and when to take it is a question for a pharmacist or a doctor (Herxheimer 2002; cautions on page 18). |
| Liira et al., Cochrane 2014 (15 RCTs, n=718).Moderate | Melatonin after a night shift added about 24 minutes to daytime sleep and 17 minutes to night-time sleep, with no gain in any other sleep measure and no dose-response. Rated low quality by the reviewers, which is why the shift-work case is weaker than the jet-lag one.Used on page 62 Full citationLiira et al. Pharmacological interventions for sleepiness and sleep disturbances caused by shift work. Cochrane Database Syst Rev. 2014;2014:CD009776. doi:10.1002/14651858.CD009776.pub2 · PMID 25113164 What the book does with itp62“Jet lag is the stronger case, shift work the weaker one (Liira 2014).” And on page 62 the reader is told · The move on that pageEat Meal timing is its own clock cue. Flying, skip the airline meal served at your 2am and eat at the destination’s next real mealtime, unless medicines, diabetes, pregnancy or an eating disorder keep meals on a schedule. On nights, avoid a heavy meal in the biological night. Alcohol on the flight costs you the back half of the first night. Melatonin is the other lever. Jet lag is the stronger case, shift work the weaker one (Liira 2014). In some countries it is a prescription medicine, so whether and when to take it is a question for a pharmacist or a doctor (Herxheimer 2002; cautions on page 18). |
| Jaehne et al., Sleep Med Rev 2009 (review, 52 studies).Emerging | Nicotine use: longer sleep onset, more fragmentation, less slow-wave sleep, and REM suppression in most studies. A narrative review with no pooling.Used on page 26 Full citationJaehne et al. Effects of nicotine on sleep during consumption, withdrawal and replacement therapy. Sleep Med Rev. 2009;13:363-77. doi:10.1016/j.smrv.2008.12.003 · PMID 19345124 What the book does with itp26Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Stutz, Eiholzer & Spengler, Sports Med 2019 (meta, 23 studies).Established | Evening exercise raised slow-wave sleep by about 1.3 percentage points. Vigorous work close to bed may delay sleep onset instead.Used on page 24 Full citationStutz, Eiholzer & Spengler. Effects of Evening Exercise on Sleep in Healthy Participants: A Systematic Review and Meta-Analysis. Sports Med. 2019;49:269-287. doi:10.1007/s40279-018-1015-0 · PMID 30374942 What the book does with itp24Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Härtter et al., Clin Pharmacol Ther 2000 (n=5 healthy men).Emerging | Fluvoxamine raised melatonin exposure roughly seventeen-fold. Five participants, all men, and the basis for the avoid advice.Used on page 18 Full citationHärtter et al. Increased bioavailability of oral melatonin after fluvoxamine coadministration. Clin Pharmacol Ther. 2000;67:1-6. doi:10.1067/mcp.2000.104071 · PMID 10668847 What the book does with itp18“The product information says to avoid melatonin with fluvoxamine, which raises what a dose delivers many-fold (Circadin SmPC 4.5; Härtter 2000; figure in the sources).” |
| Erland & Saxena, J Clin Sleep Med 2017 (31 products).Emerging | Melatonin content ran from far below the label dose to several times above it, and batches of the same product varied by as much as 465%. Serotonin turned up in eight products, which a later US assay of gummies did not find. A laboratory assay of Canadian products. No trial.Used on page 18 Full citationErland & Saxena. Melatonin Natural Health Products and Supplements: Presence of Serotonin and Significant Variability of Melatonin Content. J Clin Sleep Med. 2017;13:275-281. doi:10.5664/jcsm.6462 · PMID 27855744 What the book does with itp18“Tested supplements have run from far below the label dose to several times above it, and batches of the same product have varied by nearly five-fold (Erland 2017).” |
| Cohen et al., JAMA 2023 (25 US gummy products).Emerging | Melatonin ran from 74% to 347% of the labeled dose, and 22 of the 25 sat outside 10% of the label. Five declared CBD as an ingredient and carried 10.6 to 31.3 mg a serving, measured close to their label. One product had no melatonin detectable. One sample per brand and gummies only, so it describes a sample of products rather than the market. No serotonin was found.Used on page 18 Full citationCohen et al. Quantity of Melatonin and CBD in Melatonin Gummies Sold in the US. JAMA. 2023;329:1401-1402. doi:10.1001/jama.2023.2296 · PMID 37097362 What the book does with itp18“In 25 US gummies, 22 missed the label and five were melatonin and CBD combinations (Cohen 2023).” |
| Haghayegh et al., Sleep Med Rev 2019 (17 studies).Established | A bath at 40 to 42.5°C for at least ten minutes, one to two hours before bed, shortens sleep onset. Pooled from small studies, so the direction is firmer than the size.Used on page 24 Full citationHaghayegh et al. Before-bedtime passive body heating by warm shower or bath to improve sleep: A systematic review and meta-analysis. Sleep Med Rev. 2019;46:124-135. doi:10.1016/j.smrv.2019.04.008 · PMID 31102877 What the book does with itp24Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Singh et al., Cochrane 2023 (blue-light filtering lenses).Moderate | No benefit for eye strain or visual acuity. On sleep, which is what I cite it for, the review is indeterminate rather than negative, so the direction is not settled and I grade it there.Used on page 20 Full citationSingh et al. Blue-light filtering spectacle lenses for visual performance, sleep, and macular health in adults. Cochrane Database Syst Rev. 2023;8:CD013244. doi:10.1002/14651858.CD013244.pub2 · PMID 37593770 What the book does with itp20Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 20 the reader is told · In shortEnough sleep and a regular schedule, together, then a dim last half hour. Do not cut sleep to keep the clock. If bad sleep has run for months, that is a doctor’s problem |
| Pasquier et al., J Therm Biol 2025 (9 RCTs).Moderate | Cooling bedding moved no sleep measure. Small trials of consumer products with short durations, so read the null as being about what was tested.Used on page 20 Full citationPasquier et al. Does body cooling facilitated by bedding compared to control condition improve sleep among adults (18-64 years old)? A systematic review and meta-analysis. J Therm Biol. 2025;127:104030. doi:10.1016/j.jtherbio.2024.104030 · PMID 39708549 Published online the year before its printed issue; the printed year is shown. What the book does with itp20Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 20 the reader is told · In shortEnough sleep and a regular schedule, together, then a dim last half hour. Do not cut sleep to keep the clock. If bad sleep has run for months, that is a doctor’s problem |
| Riedy et al., Sleep Med Rev 2021 (narrative review, 38 articles).Emerging | Continuous white noise as a sleep aid. A narrative synthesis rather than a pooling, with findings running both ways and the certainty for benefit rated very low. The reviewers note that continuous noise may also affect sleep and hearing adversely.Used on page 20 Full citationRiedy et al. Noise as a sleep aid: A systematic review. Sleep Med Rev. 2021;55:101385. doi:10.1016/j.smrv.2020.101385 · PMID 33007706 Published online the year before its printed issue; the printed year is shown. What the book does with itp20Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 20 the reader is told · In shortEnough sleep and a regular schedule, together, then a dim last half hour. Do not cut sleep to keep the clock. If bad sleep has run for months, that is a doctor’s problem |
| Wang et al., Sleep Med 2025.Moderate | Exercise raised slow-wave sleep by about two minutes in adults who already had a diagnosed sleep disorder, most of it in sleep apnea. Every participant had a disorder, so it carries no comparison against good sleepers. A pooling of small, short trials.Used on pages 23, 24 Full citationWang et al. Comparative efficacy of exercise modalities on sleep architecture in adults with sleep disorders: a systematic review and network meta-analysis of randomized controlled trials. Sleep Med. 2025;134:106680. doi:10.1016/j.sleep.2025.106680 · PMID 40675043 What the book does with itp23“In adults who already have a diagnosed sleep disorder, a separate pooling found about two extra minutes of slow-wave sleep, most of it in sleep apnea (Wang 2025).” And on page 23 the reader is told · Remember thisTraining buys minutes of deep sleep, and a nightcap costs you the rest of the night |
| Gardiner et al., Sleep Med Rev 2024 (meta, 27 studies).Established | Alcohol before bed delayed and shortened REM, in a dose-response: disruption from about two standard drinks (0.5 g/kg) and worse with more. Total sleep time and waking were pooled with wide uncertainty. The fragmentation claim rests on Ebrahim rather than on this pooling.Used on pages 26, 63 Full citationGardiner et al. The effect of alcohol on subsequent sleep in healthy adults: A systematic review and meta-analysis. Sleep Med Rev. 2024;80:102030. doi:10.1016/j.smrv.2024.102030 · PMID 39631226 What the book does with itp26“Alcohol suppresses REM in a dose-response: about two standard drinks cut it, and larger doses cut it further (Gardiner 2024).” |
| Gardiner et al., Sleep Med Rev 2023 (meta).Strong | Caffeine harms sleep continuity and duration; REM share largely unaffected. Pooled experimental studies with a dose-response across them, large enough to settle the direction.Used on pages 10, 13, 26, 58, 60 Full citationGardiner et al. The effect of caffeine on subsequent sleep: A systematic review and meta-analysis. Sleep Med Rev. 2023;69:101764. doi:10.1016/j.smrv.2023.101764 · PMID 36870101 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p13“Gardiner 2023 pooled 24 studies: 8.8 hours for a 107 mg coffee, and 13.2 hours for a 217.5 mg pre-workout scoop.” And on page 13 the reader is told · In shortCheck off enough sleep at a regular time, eat better, and start moving. Ask your clinician how these apply if you take a regular medicine, are pregnant, or have a diagnosed condition p26“Alcohol suppresses REM in a dose-response: about two standard drinks cut it, and larger doses cut it further (Gardiner 2024).” |
| Li et al., Nat Commun 2026 (UK Biobank accelerometry, n=85,618).Emerging | Short sleep followed by rebound was not associated with higher mortality, while short sleep without rebound was. Observational, and the authors say it cannot settle cause and may reflect underlying frailty.Used on page 21 Full citationLi et al. Acute sleep rebound following sleep restriction is associated with reduced mortality risk. Nat Commun. 2026;17. doi:10.1038/s41467-026-72461-1 · PMID 42045198 What the book does with itp21“One accelerometer cohort found short sleep followed by rebound did not carry the higher mortality short sleep without rebound did (Li 2026).” And on page 21 the reader is told · The one to keepHold the wake time within about half an hour on the days the night was long enough (a convention). After a short night, the extra sleep comes first; it is the sleeping in without a deficit that drifts the clock |
| Chaput et al., Sleep 2024 (UK Biobank accelerometry, n=73,513).Emerging | Weekend catch-up tracked with neither mortality nor cardiovascular disease. Same biobank as Li, opposite conclusion, because the two define catching up differently. Printed so the disagreement is visible.Used on page 21 Full citationChaput et al. Device-measured weekend catch-up sleep, mortality, and cardiovascular disease incidence in adults. Sleep. 2024;47. doi:10.1093/sleep/zsae135 · PMID 38895883 What the book does with itp21“Another in the same biobank found weekend catch-up tracked with nothing (Chaput 2024).” And on page 21 the reader is told · The one to keepHold the wake time within about half an hour on the days the night was long enough (a convention). After a short night, the extra sleep comes first; it is the sleeping in without a deficit that drifts the clock |
| Windred et al., Sleep 2024 (UK Biobank, n=60,977).Moderate | Regularity out-predicted duration; the top four quintiles had 20 to 48% lower mortality than the bottom. Observational.Used on pages 10, 17, 19, 21, 59, 63, 67 Full citationWindred et al. Sleep regularity is a stronger predictor of mortality risk than sleep duration: A prospective cohort study. Sleep. 2024;47. doi:10.1093/sleep/zsad253 · PMID 37738616 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p19“The more regular sleepers had much lower all-cause, cancer and cardiometabolic mortality, and regularity out-predicted duration with both in the same model (Windred 2024).” And on page 19 the reader is told · How to use itIf you fix one thing in this chapter, fix the wake time, once the night is long enough. It is the easiest end of the night to hold p21“The tested part is the tracker cohort on page 19: irregular timing tracked worse outcomes (Windred 2024).” And on page 21 the reader is told · The one to keepHold the wake time within about half an hour on the days the night was long enough (a convention). After a short night, the extra sleep comes first; it is the sleeping in without a deficit that drifts the clock |
| Cappuccio et al., Sleep 2010 (meta of cohorts).Moderate | Duration U-curve, lowest risk near seven hours. Self-reported duration, and the long-sleep arm is partly reverse causation.Used on pages 17, 19 Full citationCappuccio et al. Sleep duration and all-cause mortality: a systematic review and meta-analysis of prospective studies. Sleep. 2010;33:585-92. doi:10.1093/sleep/33.5.585 · PMID 20469800 What the book does with itp19“Pooled cohorts find a U-shaped curve, with the lowest risk near seven hours and risk rising on both sides (Cappuccio 2010; Yin 2017).” And on page 19 the reader is told · How to use itSeven to nine hours is the usual adult range, and your own need sits somewhere in it. Stop treating more as automatically better |
| Yin et al., J Am Heart Assoc 2017 (meta of cohorts).Moderate | The same U-shaped duration curve in a later pooling. Self-reported duration, with the same caveat on the long-sleep arm.Used on pages 17, 19 Full citationYin et al. Relationship of Sleep Duration With All-Cause Mortality and Cardiovascular Events: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies. J Am Heart Assoc. 2017;6. doi:10.1161/JAHA.117.005947 · PMID 28889101 What the book does with itp19“Pooled cohorts find a U-shaped curve, with the lowest risk near seven hours and risk rising on both sides (Cappuccio 2010; Yin 2017).” And on page 19 the reader is told · How to use itSeven to nine hours is the usual adult range, and your own need sits somewhere in it. Stop treating more as automatically better |
| Khalsa et al., J Physiol 2003 (phase-response curve, n=21); St Hilaire et al., J Physiol 2012 (one-hour light pulse, same curve shape).Emerging | Light at or slightly after habitual bedtime delays the clock, and light at or slightly before habitual waketime advances it. The phase-response curve the morning-daylight instruction rests on. It measures bright laboratory light rather than ten minutes outside a front door, and is graded on the 2003 study. The ten minutes is a dose I set; the study set none.Used on page 62 Full citationKhalsa et al. A phase response curve to single bright light pulses in human subjects. J Physiol. 2003;549:945-52. doi:10.1113/jphysiol.2003.040477 · PMID 12717008 St Hilaire et al. Human phase response curve to a 1 h pulse of bright white light. J Physiol. 2012;590:3035-45. doi:10.1113/jphysiol.2012.227892 · PMID 22547633 What the book does with itp62Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 62 the reader is told · The move on that pageExercise Daylight at the right end of the day anchors the clock, and a walk is the easy way to get it. On a shift, bright light and some movement early hold alertness; wind down before the daytime block. On the flight, get up and move every couple of hours. If a calf swells or aches in the days after, that is a same-day question; with breathlessness, chest pain or coughing blood alongside it, an emergency call. Both are on page 72. |
| Chang et al., PNAS 2015 (crossover, n=12).Emerging | Evening screen light delayed melatonin and the clock. Twelve people, at a deliberately strong light dose.Used on page 19 Full citationChang et al. Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proc Natl Acad Sci U S A. 2015;112:1232-7. doi:10.1073/pnas.1418490112 · PMID 25535358 Published online the year before its printed issue; the printed year is shown. What the book does with itp19“The tablet readers released melatonin later, took longer to fall asleep, had less REM, and woke sleepier (Chang 2015).” p19“Chang and colleagues had volunteers read for four hours before bed on a light-emitting tablet at full brightness, or on paper, then measured what happened to melatonin and to the body clock.” And on page 19 the reader is told · How to use itI believe this can be read as evidence about light before bed. Dim the room in the last half hour |
| Luboshitzky et al., J Androl 2002 (crossover, n=8).Emerging | 3 mg daily, three months per arm of a six-month crossover, in healthy men. Serum testosterone and gonadotropins did not change; sperm concentration and motility fell in two of the eight, which the authors call preliminary and which no one has replicated. Eight men, and dosed at 5pm rather than bedtime.Used on page 73 Full citationLuboshitzky et al. Melatonin administration alters semen quality in healthy men. J Androl. 2002;23:572-8. doi:10.1002/j.1939-4640.2002.tb02281.x · PMID 12065466 What the book does with itp73“Testosterone did not move, but sperm quality fell in two of them, far too few to establish a risk, and dosed at 5pm rather than bedtime (Luboshitzky 2002).” And on page 73 the reader is told · In shortThe differences are mostly timing and weighting. The exercise and heart evidence was built on men, so let your own response correct those numbers |
| Held et al., Pharmacopsychiatry 2002 (crossover, n=12).Emerging | Oral magnesium raised slow-wave sleep and delta power against placebo in adults aged 60 to 80, measured by polysomnography. One crossover in twelve older adults, and it does not report what the gain is worth in minutes.Used on pages 24, 50 Full citationHeld et al. Oral Mg(2+) supplementation reverses age-related neuroendocrine and sleep EEG changes in humans. Pharmacopsychiatry. 2002;35:135-43. doi:10.1055/s-2002-33195 · PMID 12163983 What the book does with itp24“Off the shelf there is one candidate: a single crossover in twelve older adults, where oral magnesium raised slow-wave sleep (Held 2002).” p50“Creatine and protein powder are trial-backed; vitamin D covers a low test or the winter schedule; for magnesium and deep sleep the case is one small crossover with sleep recording (Held 2002).” And on page 50 the reader is told · Remember thisChange one optional supplement at a time, cleared with a pharmacist. If nothing you can observe has moved in a couple of months, stop paying for it. That rule is for the extras, never for a preventive dose like folic acid or vitamin D, or anything a clinician told you to take |
| Kunz et al., J Clin Endocrinol Metab 2004 (two RCTs, n=14 combined).Moderate | 3 mg for four weeks raised REM percentage against placebo, replicated across two small trials. Patients were enrolled for a REM deficit at least 25% below their age norm, so this corrects a shortfall and says nothing about a normal sleeper. Fourteen people in total, which is why it does not go higher.Used on page 20 Full citationKunz et al. Melatonin in patients with reduced REM sleep duration: two randomized controlled trials. J Clin Endocrinol Metab. 2004;89:128-34. doi:10.1210/jc.2002-021057 · PMID 14715839 What the book does with itp20“The randomized evidence that raised it, two small trials, enrolled patients for a REM deficit, so it corrected a shortfall rather than adding to a normal night (Kunz 2004).” And on page 20 the reader is told · In shortEnough sleep and a regular schedule, together, then a dim last half hour. Do not cut sleep to keep the clock. If bad sleep has run for months, that is a doctor’s problem |
| Ebrahim et al., Alcohol Clin Exp Res 2013 (narrative review).Emerging | Alcohol suppresses REM and fragments the second half of the night. A narrative review with no pooling.Used on pages 24, 25, 26 Full citationEbrahim et al. Alcohol and sleep I: effects on normal sleep. Alcohol Clin Exp Res. 2013;37:539-49. doi:10.1111/acer.12006 · PMID 23347102 What the book does with itp25“Reviews of alcohol and sleep find it is the clearest disruptor, suppressing REM and fragmenting the back half of the night as it wears off (Ebrahim 2013, a narrative review).” And on page 25 the reader is told · Remember thisCutting the morning short mostly costs REM. Nothing sold is shown to put it back, in the trials I found |
| Qaseem et al. (ACP), Ann Intern Med 2016.Guidance | CBT-I is first-line for chronic insomnia, ahead of medication.Used on pages 10, 19, 21, 58 Full citationQaseem et al. (ACP). Management of Chronic Insomnia Disorder in Adults: A Clinical Practice Guideline From the American College of Physicians. Ann Intern Med. 2016;165:125-33. doi:10.7326/M15-2175 · PMID 27136449 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p19“The American College of Physicians recommends cognitive behavioral therapy for insomnia as the initial treatment for chronic insomnia in adults, ahead of medication (Qaseem 2016).” And on page 19 the reader is told · How to use itIf you have three or more bad nights a week for at least three months, with your days affected: ask for CBT-I by name p21“The American College of Physicians and the sleep academy put it ahead of medication (Qaseem 2016; Edinger 2021).” And on page 21 the reader is told · The one to keepHold the wake time within about half an hour on the days the night was long enough (a convention). After a short night, the extra sleep comes first; it is the sleeping in without a deficit that drifts the clock |
| Brooks & Lack, Sleep 2006 (crossover, n=24).Emerging | Compared 5, 10, 20 and 30 minute naps after a five-hour night. Five minutes did little. Ten gave the benefit on waking, twenty took about thirty-five minutes to arrive, thirty produced grogginess first. One small crossover, measured across the afternoon only, so it cannot say what a nap costs the next night.Used on page 21 Full citationBrooks & Lack. A brief afternoon nap following nocturnal sleep restriction: which nap duration is most recuperative? Sleep. 2006;29:831-40. doi:10.1093/sleep/29.6.831 · PMID 16796222 What the book does with itp21“A twenty-minute nap took about thirty-five minutes to pay off; a thirty-minute nap left people groggy first (Brooks & Lack 2006, 24 adults after a short night).” And on page 21 the reader is told · The one to keepHold the wake time within about half an hour on the days the night was long enough (a convention). After a short night, the extra sleep comes first; it is the sleeping in without a deficit that drifts the clock |
Eat
| The source | What the book says it shows, and where |
|---|---|
| Bermingham et al., Nat Med 2024 (RCT, n=347).Moderate | An 18-week personalized program using postprandial responses, microbiome and history beat US guideline advice on weight, by about 2.5 kg. Of two co-primary endpoints, triglycerides improved and LDL cholesterol did not; weight was a secondary outcome. Held a tier below its design for both reasons.Used on pages 35, 56 Full citationBermingham et al. Effects of a personalized nutrition program on cardiometabolic health: a randomized controlled trial. Nat Med. 2024;30:1888-1897. doi:10.1038/s41591-024-02951-6 · PMID 38714898 What the book does with itp35“Weight was a secondary outcome, and the other co-primary was null, in 347 people (Bermingham 2024).” And on page 35 the reader is told · Remember thisAdd fiber a few grams a week, with water (a convention) p56“It had two co-primary endpoints: triglycerides improved and LDL cholesterol did not (Bermingham 2024).” And on page 56 the reader is told · How to use itKeep the plate advice as your default; use n-of-1 for low-risk habits such as a wind-down. Never run a food challenge on yourself: a possible allergic reaction or unexplained symptoms go to a clinician first (NHS) |
| Zeevi et al., Cell 2015 (cohort, n=800).Moderate | Glucose responses to identical meals differ. A short-term marker.Used on pages 35, 56 Full citationZeevi et al. Personalized Nutrition by Prediction of Glycemic Responses. Cell. 2015;163:1079-1094. doi:10.1016/j.cell.2015.11.001 · PMID 26590418 What the book does with itp35“People differ in how the same meal moves their blood sugar, across 800 of them (Zeevi 2015).” And on page 35 the reader is told · Remember thisAdd fiber a few grams a week, with water (a convention) p56“The same foods produced sharply different blood-sugar responses between people, enough that the authors suggested universal dietary advice may have limited utility (Zeevi 2015).” p56“The Zeevi study put glucose monitors on 800 people and logged 46,898 meals.” And on page 56 the reader is told · How to use itKeep the plate advice as your default; use n-of-1 for low-risk habits such as a wind-down. Never run a food challenge on yourself: a possible allergic reaction or unexplained symptoms go to a clinician first (NHS) |
| Hakam et al., JAMA Netw Open 2024 (systematic review, 18 RCTs).Moderate | Trials of adding water: fewer recurrent kidney stones and some weight loss in a few trials, single trials on migraine, urinary infection, diabetes and low blood pressure; the authors call the evidence limited. The book’s water line rests on this rather than on an absence of trials.Used on page 34 Full citationHakam et al. Outcomes in Randomized Clinical Trials Testing Changes in Daily Water Intake: A Systematic Review. JAMA Netw Open. 2024;7:e2447621. doi:10.1001/jamanetworkopen.2024.47621 · PMID 39585691 What the book does with itp34“Past thirst, extra water has trial support only in a few specific groups, people who form kidney stones above all (Hakam 2024); for everyone else the evidence is thin, and drinking far past it during long events can dangerously dilute blood sodium.” |
| Te Morenga et al., BMJ 2012 (30 RCTs, 38 cohorts).Moderate | Cutting sugar ad libitum, −0.80 kg. Swapping it for the same calories of other carbohydrate, +0.04 kg: no effect. The review graded its own evidence low to moderate, so I follow it down.Used on page 29 Full citationTe Morenga et al. Dietary sugars and body weight: systematic review and meta-analyses of randomised controlled trials and cohort studies. BMJ. 2012;346:e7492. doi:10.1136/bmj.e7492 · PMID 23321486 What the book does with itp29Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| SACN 2015; NDNS 2019 to 2023 (UK); NHANES (US); HealthHub (HPB), Singapore.Guidance | The 30 g fiber recommendation, which is what the Guidance label here refers to; HPB sets Singapore’s 20 g for women and 26 g for men. The survey means behind the shortfall are descriptive and carry no grade: about 16 g in UK surveys and 17 g in US NHANES, with about 4% of UK adults and roughly one in twenty US adults reaching the target.Used on page 33 Full citationScientific Advisory Committee on Nutrition (SACN). SACN Carbohydrates and Health report. 2015. gov.uk/government/publications/sacn-carbohydrates-and-health-report Office for Health Improvement and Disparities (Department of Health and Social Care). National Diet and Nutrition Survey 2019 to 2023. 2025. gov.uk/government/statistics/national-diet-and-nutrition-survey-2019-to-2023 Centers for Disease Control and Prevention, National Center for Health Statistics. National Health and Nutrition Examination Survey (NHANES). cdc.gov/nchs/nhanes/index.html HealthHub (Ministry of Health Singapore / Health Promotion Board). HealthHub. healthhub.sg What the book does with itp33“Survey means, UK NDNS, and US NHANES.” |
| Hall et al., Cell Metab 2019 (inpatient RCT, n=20).Emerging | On matched menus, people ate about 500 kcal a day more on the ultra-processed arm. One inpatient trial of 20 people: the strongest causal design here, and still one small trial.Used on page 30 Full citationHall et al. Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake. Cell Metab. 2019;30:67-77.e3. doi:10.1016/j.cmet.2019.05.008 · PMID 31105044 What the book does with itp30“An earlier inpatient trial pointed one way: 20 adults ate about 500 calories a day more on the ultra-processed arm of two matched menus (Hall 2019).” And on page 30 the reader is told · How to use itSwap where you can, starting with the three biggest sources: sugary drinks, packaged snacks and processed meat. Convenience food is not always a choice, and a swapped item beats a cut you cannot keep |
| Sacks et al., Circulation 2017 (AHA Presidential Advisory).Guidance | Replacing saturated fat with unsaturated fat lowers cardiovascular risk, which is the basis for the line that with fat the type matters most. The book names it in a source line as the AHA Presidential Advisory.Used on pages 10, 34 Full citationSacks et al. Dietary Fats and Cardiovascular Disease: A Presidential Advisory From the American Heart Association. Circulation. 2017;136:e1-e23. doi:10.1161/CIR.0000000000000510 · PMID 28620111 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed |
| McDonald et al., mSystems 2018 (American Gut, cross-sectional).Emerging | The thirty-plants-a-week figure. Self-selected participants, and a small contrast within the sample. No trial.Used on page 36 Full citationMcDonald et al. American Gut: an Open Platform for Citizen Science Microbiome Research. mSystems. 2018;3. doi:10.1128/mSystems.00031-18 · PMID 29795809 What the book does with itp36“The thirty-a-week figure comes from cross-sectional citizen-science data (McDonald 2018): untested, so hold it loosely.” p36“What tracked with a more diverse microbiome in that survey was the number of plant types eaten (McDonald 2018); rarity and price did not come into it.” |
| Garegnani et al., Cochrane 2026 (22 trials, n=1,995).Moderate | Intermittent fasting against ordinary dietary advice: little to no difference in weight, low certainty. Against no intervention, about 3.4% of body weight at moderate certainty; the authors read that as likely little to no difference against their 5% clinical benchmark. No follow-up beyond 12 months.Used on page 30 Full citationGaregnani et al. Intermittent fasting for adults with overweight or obesity. Cochrane Database Syst Rev. 2026;2:CD015610. doi:10.1002/14651858.CD015610.pub2 · PMID 41692034 What the book does with itp30“Against no advice at all it averaged about 3.4% of body weight, which the review itself still reads as likely little to no difference (Garegnani 2026).” And on page 30 the reader is told · How to use itIn this trial the window added nothing beyond the calorie cut for weight. If a window helps you eat less, that is what it is doing; on diabetes medicines, the cautions on page 71 come first. Whether timing moves anything besides weight is still open |
| Liu et al., NEJM 2022 (RCT, n=139).Established | Time-restricted eating added nothing to the same calorie cut over 12 months.Used on pages 29, 30 Full citationLiu et al. Calorie Restriction with or without Time-Restricted Eating in Weight Loss. N Engl J Med. 2022;386:1495-1504. doi:10.1056/NEJMoa2114833 · PMID 35443107 What the book does with itp30“There was no significant difference in weight loss or metabolic markers (Liu 2022).” p30“For twelve months, Liu and colleagues randomized 139 adults with obesity to eating 8am to 4pm plus a calorie cut, or the same cut with no window.” And on page 30 the reader is told · How to use itIn this trial the window added nothing beyond the calorie cut for weight. If a window helps you eat less, that is what it is doing; on diabetes medicines, the cautions on page 71 come first. Whether timing moves anything besides weight is still open |
| Dicken et al., Nat Med 2025 (crossover, n=55).Emerging | Nature Medicine has since published correspondence disputing the conclusions, which is part of why it stays at this grade. Minimally processed beat ultra-processed by ~1 percentage point of body weight over eight weeks. All had overweight or obesity and already ate mostly ultra-processed food. No penalty on lipids or glucose. One crossover standing on its own, so the rubric caps it here.Used on page 30 Full citationDicken et al. Ultraprocessed or minimally processed diets following healthy dietary guidelines on weight and cardiometabolic health: a randomized, crossover trial. Nat Med. 2025;31:3297-3308. doi:10.1038/s41591-025-03842-0 · PMID 40760353 What the book does with itp30“With diet quality held constant, the minimally processed arm still came out ahead by about one percentage point of body weight over eight weeks (Dicken 2025).” And on page 30 the reader is told · How to use itSwap where you can, starting with the three biggest sources: sugary drinks, packaged snacks and processed meat. Convenience food is not always a choice, and a swapped item beats a cut you cannot keep |
| Martinez Steele et al., BMJ Open 2016 (NHANES).Emerging | Ultra-processed food supplied ~57.9% of US dietary energy. Cross-sectional survey data.Used on page 31 Full citationMartinez Steele et al. Ultra-processed foods and added sugars in the US diet: evidence from a nationally representative cross-sectional study. BMJ Open. 2016;6:e009892. doi:10.1136/bmjopen-2015-009892 · PMID 26962035 What the book does with itp31“Ultra-processed foods made up 57.9% of dietary energy (Martinez Steele 2016).” p31“Martinez Steele 2016, from a national dietary survey.” And on page 31 the reader is told · How to use itYou do not have to hunt for ultra-processed food to cut it. It is already most of the calories, so swapping it out where you can means changing the default. Sugary drinks are the easiest place to start |
| Zmora, Suez et al., Cell 2018.Emerging | Probiotic colonization of the gut mucosa is person-specific and often transient, measured by endoscopy, which is why stool testing misses it. A small mechanistic study measuring colonization rather than benefit.Used on page 36 Full citationZmora, Suez et al. Personalized Gut Mucosal Colonization Resistance to Empiric Probiotics Is Associated with Unique Host and Microbiome Features. Cell. 2018;174:1388-1405.e21. doi:10.1016/j.cell.2018.08.041 · PMID 30193112 What the book does with itp36“Named-strain trials are small and mixed; none I graded supports picking one, and colonization is person-specific and often transient (Zmora & Suez 2018).” |
| Morton et al., BJSM 2018 (49 RCTs, n≈1,900).Strong | Protein plus training; benefit flattens above ~1.6 g/kg.Used on pages 10, 29, 32, 42, 46 Full citationMorton et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018;52:376-384. doi:10.1136/bjsports-2017-097608 · PMID 28698222 Published online the year before its printed issue; the printed year is shown. What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p32“The gains at any dose are modest, and they came with training attached, which is the only way the pooled trials tested it (Morton 2018).” p32“That band comes from the older-adult and training literature (Bauer 2013; Phillips 2016; Morton 2018), and no women-specific trial sets it.” And on page 32 the reader is told · Remember thisAim at these numbers; going past the protein figure buys little. Test for a micronutrient only when your diet, symptoms or medicines give a reason to p42“Protein supplies the material (Morton 2018), recovery banks it (Saner 2020), and the training itself raises slow-wave sleep (Kredlow 2015).” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can |
| Phillips, Chevalier & Leidy, Appl Physiol Nutr Metab 2016 (review).Emerging | At least 1.2 to 1.6 g/kg a day as a more ideal protein target for adults: the band the plate chapter uses.Used on pages 29, 32, 46, 68 Full citationPhillips, Chevalier & Leidy. Protein "requirements" beyond the RDA: implications for optimizing health. Appl Physiol Nutr Metab. 2016;41:565-72. doi:10.1139/apnm-2015-0550 · PMID 26960445 What the book does with itp32“That band comes from the older-adult and training literature (Bauer 2013; Phillips 2016; Morton 2018), and no women-specific trial sets it.” And on page 32 the reader is told · Remember thisAim at these numbers; going past the protein figure buys little. Test for a micronutrient only when your diet, symptoms or medicines give a reason to p46“About 1.2 to 1.6 g/kg spread over your meals covers it (Phillips 2016; Morton 2018).” p68“Treat 1.0 to 1.2 g/kg as the floor (Bauer 2013), and aim nearer 1.2 to 1.6 if you are lifting (Phillips 2016).” And on page 68 the reader is told · The move on that pageEat Protein matters more now. Treat 1.0 to 1.2 g/kg as the floor (Bauer 2013), and aim nearer 1.2 to 1.6 if you are lifting (Phillips 2016). Spread it across meals. With kidney disease, a reason to suspect it, or restricted protein, agree on the target with your doctor. |
| Reynolds et al., Lancet 2019 (185 cohorts, ~135m person-years; 58 trials).Moderate | Higher fiber intake tracked with 15 to 30% lower mortality and less major disease. The authors’ own GRADE certainty is moderate, in people without chronic disease.Used on pages 10, 29, 30 Full citationReynolds et al. Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. Lancet. 2019;393:434-445. doi:10.1016/S0140-6736(18)31809-9 · PMID 30638909 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p30“Dose-response throughout, with 15 to 30% lower mortality at the highest intakes (Reynolds 2019).” p30“Reynolds and colleagues pooled the fiber and whole grain evidence for the World Health Organization.” And on page 30 the reader is told · How to use itTargets differ by country: Singapore sets 20 g a day for women and 26 g for men, the US Daily Value is 28 g, UK guidance says 30 g. The pooled benefit rises across the range with no threshold where it switches on |
| Lane et al., BMJ 2024 (umbrella review, 45 pooled analyses, n≈9.9m).Moderate | Ultra-processed food intake tracked with worse outcomes across 32 of 45 endpoints, but GRADE quality low or very low for 41. Observational, very broad exposure.Used on pages 29, 30 Full citationLane et al. Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses. BMJ. 2024;384:e077310. doi:10.1136/bmj-2023-077310 · PMID 38418082 What the book does with itp30“Higher intake was associated with worse outcomes, consistently enough to act on (Lane 2024).” p30“Lane and colleagues ran one on ultra-processed food across dozens of outcomes.” And on page 30 the reader is told · How to use itSwap where you can, starting with the three biggest sources: sugary drinks, packaged snacks and processed meat. Convenience food is not always a choice, and a swapped item beats a cut you cannot keep |
| Mamerow et al., J Nutr 2014 (crossover, n=8).Emerging | Even distribution raised 24-hour muscle protein synthesis 25%. Eight participants, a surrogate endpoint, and later trials found no difference and have no entry of their own; the book keeps an even spread as a default while saying the daily total matters more.Used on page 31 Full citationMamerow et al. Dietary protein distribution positively influences 24-h muscle protein synthesis in healthy adults. J Nutr. 2014;144:876-80. doi:10.3945/jn.113.185280 · PMID 24477298 What the book does with itp31“The even split produced more synthesis over the day (Mamerow 2014).” p31“In eight adults, Mamerow measured muscle protein synthesis over 24 hours.” And on page 31 the reader is told · How to use itAn even spread is the pattern I would use: a protein source at every meal, with dinner carrying no more than its share. The trial rests on eight people, so the daily total still matters more |
| Zhao et al., JAMA Netw Open 2023.Moderate | The apparent benefit of moderate drinking is mostly a study artifact. 107 observational cohorts, whose point is that the corpus is confounded.Used on pages 12, 24, 29, 31 Full citationZhao et al. Association Between Daily Alcohol Intake and Risk of All-Cause Mortality: A Systematic Review and Meta-analyses. JAMA Netw Open. 2023;6:e236185. doi:10.1001/jamanetworkopen.2023.6185 · PMID 37000449 What the book does with itp12“That is the same design problem Zhao 2023 identifies, sitting inside the score.” And on page 12 the reader is told · In shortRead the figure as the size of the association around basic habits, and how stacking them tracks with a meaningful difference p31“Among the abstainers being compared are people who stopped drinking because they were already unwell (Zhao 2023).” p31“Re-analyzing the literature, Zhao and colleagues find that it is mostly an artifact of study design.” And on page 31 the reader is told · How to use itDo not start drinking for your health. For sleep specifically, none within about three hours of bed. Three hours is a conventional clearance gap, so treat it as a starting point and move it earlier if your sleep still suffers |
Across sexes and life stages
| The source | What the book says it shows, and where |
|---|---|
| Kravitz et al., Sleep 2008 (SWAN, n=3,045).Moderate | Sleep problems rose through the transition; vasomotor symptoms tracked the worse nights.Used on pages 24, 74 Full citationKravitz et al. Sleep disturbance during the menopausal transition in a multi-ethnic community sample of women. Sleep. 2008;31:979-90. PMID 18652093 What the book does with itp24“Through the menopausal transition, night sweats track with broken nights (Kravitz 2008).” p74“Vasomotor symptoms, night sweats among them, tracked closely with the worse nights (Kravitz 2008).” And on page 74 the reader is told · What to do about itNight sweats that break sleep are treatable in their own right, a doctor’s conversation (page 72); the cool room and the fixed wake time still help |
| Watson et al., J Bone Miner Res 2018 (LIFTMOR, RCT, n=101, 8 months).Moderate | Supervised heavy lifting twice a week in women with low bone mass: spine density +2.9% against −1.2% in controls, one minor adverse event. Small, single-center, supervised, and the endpoint is density rather than fractures.Used on pages 43, 73 Full citationWatson et al. High-Intensity Resistance and Impact Training Improves Bone Mineral Density and Physical Function in Postmenopausal Women With Osteopenia and Osteoporosis: The LIFTMOR Randomized Controlled Trial. J Bone Miner Res. 2018;33:211-220. doi:10.1002/jbmr.3284 · PMID 28975661 Published online the year before its printed issue; the printed year is shown. What the book does with itp73“With a diagnosis of osteoporosis, heavy lifting is a physical therapist or doctor question first; the LIFTMOR trial was supervised (Watson 2018).” And on page 73 the reader is told · In shortThe differences are mostly timing and weighting. The exercise and heart evidence was built on men, so let your own response correct those numbers |
| Greendale et al., J Bone Miner Res 2012 (SWAN cohort, DXA).Moderate | Loss accelerated ~1 year before the final period: ~2.5% a year at the spine, ~1.8% at the neck.Used on pages 43, 74 Full citationGreendale et al. Bone mineral density loss in relation to the final menstrual period in a multiethnic cohort: results from the Study of Women’s Health Across the Nation (SWAN). J Bone Miner Res. 2012;27:111-8. doi:10.1002/jbmr.534 · PMID 21976317 What the book does with itp43“Around menopause bone loss accelerates, and lifting then is where I would put the effort (Greendale 2012).” p74“The window runs from about a year before the final period to about two years after it (Greendale 2012).” And on page 74 the reader is told · What to do about itUse the window. Load-bearing and resistance training in the years around the transition, paired with enough protein, calcium and vitamin D |
| El Khoudary et al., Circulation 2020 (AHA scientific statement).Guidance | Lipids, blood pressure and visceral fat rise across the transition. A clinical body reading observational data, so I treat it as I treat the other scientific statements here.Used on page 74 Full citationEl Khoudary et al. Menopause Transition and Cardiovascular Disease Risk: Implications for Timing of Early Prevention: A Scientific Statement From the American Heart Association. Circulation. 2020;142:e506-e532. doi:10.1161/CIR.0000000000000912 · PMID 33251828 What the book does with itp74“The statement calls the transition a critical window for prevention (El Khoudary 2020).” And on page 74 the reader is told · What to do about itGet the numbers instead of assuming them: ask whether ApoB fits your risk, take blood pressure at home, and tighten the plate and the training now |
| Black & Matkin-Hussey, Physiologia 2024 (narrative review).Emerging | Concludes only that intake should be at least the RDA, 0.8 g/kg a day. The women-specific evidence is sparse and low quality.Used on pages 32, 74 Full citationBlack & Matkin-Hussey. The Impact of Protein in Post-Menopausal Women on Muscle Mass and Strength: A Narrative Review. Physiologia. 2024;4:266-285. doi:10.3390/physiologia4030016 What the book does with itp32“It reports the women-specific evidence as sparse and of low quality (Black & Matkin-Hussey 2024).” And on page 32 the reader is told · Remember thisAim at these numbers; going past the protein figure buys little. Test for a micronutrient only when your diet, symptoms or medicines give a reason to p74“Flagged in the same review: the women-specific evidence is sparse and of low quality (Black & Matkin-Hussey 2024).” And on page 74 the reader is told · What to do about itHold the book’s targets: the upper end of 1.2 to 1.6 g/kg if you train, spread across meals, with the lifting that makes it work; kidney disease changes this, so ask. Treat any menopause-specific protein protocol as unproven |
| Bauer et al., JAMDA 2013 (PROT-AGE).Guidance | The older-adult protein consensus behind the 1.0 to 1.2 g/kg floor over 65, and the higher band for those who train.Used on pages 32, 33, 68, 74 Full citationBauer et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. J Am Med Dir Assoc. 2013;14:542-59. doi:10.1016/j.jamda.2013.05.021 · PMID 23867520 What the book does with itp32“Protein needs rise with age (Bauer 2013).” p32“That band comes from the older-adult and training literature (Bauer 2013; Phillips 2016; Morton 2018), and no women-specific trial sets it.” And on page 32 the reader is told · Remember thisAim at these numbers; going past the protein figure buys little. Test for a micronutrient only when your diet, symptoms or medicines give a reason to p33“For healthy over-65s, 1.0 to 1.2 g/kg is the usual consensus floor (Bauer 2013), and appetite, illness and a clinician’s goals move it.” p68“Treat 1.0 to 1.2 g/kg as the floor (Bauer 2013), and aim nearer 1.2 to 1.6 if you are lifting (Phillips 2016).” And on page 68 the reader is told · The move on that pageEat Protein matters more now. Treat 1.0 to 1.2 g/kg as the floor (Bauer 2013), and aim nearer 1.2 to 1.6 if you are lifting (Phillips 2016). Spread it across meals. With kidney disease, a reason to suspect it, or restricted protein, agree on the target with your doctor. |
| Patel et al., Sports Med Open 2021 (scoping review, 250 studies).Moderate | Women were about 18% of participants in the average study; over half the studies excluded them.Used on pages 39, 75 Full citationPatel et al. The Underrepresentation of Females in Studies Assessing the Impact of High-Dose Exercise on Cardiovascular Outcomes: a Scoping Review. Sports Med Open. 2021;7:30. doi:10.1186/s40798-021-00320-y · PMID 33914201 What the book does with itp39“Across 250 studies of high-dose exercise and heart outcomes, women averaged about 18% of participants (Patel 2021).” p75“Just over half the studies excluded women entirely (Patel 2021).” And on page 75 the reader is told · What to do about itRead male-heavy effect sizes as a starting point rather than a precise number for you. When a doctor quotes a risk score, ask whether it was validated in women |
| Leproult & Van Cauter, JAMA 2011 (single-arm, n=10 men).Emerging | A week at five hours cut daytime testosterone 10 to 15%. One lab, unreplicated.Used on pages 45, 46, 73 Full citationLeproult & Van Cauter. Effect of 1 week of sleep restriction on testosterone levels in young healthy men. JAMA. 2011;305:2173-4. doi:10.1001/jama.2011.710 · PMID 21632481 What the book does with itp45“In another, a single week restricted to five hours a night lowered daytime testosterone by 10 to 15% in ten healthy young men (Leproult 2011).” And on page 45 the reader is told · Remember thisFive nights at four hours cut the muscle-building signal by about 19%, though an exercise arm in the same study held it normal p73“One week restricted to five hours a night lowered daytime testosterone in healthy young men by 10 to 15% (Leproult 2011).” And on page 73 the reader is told · In shortThe differences are mostly timing and weighting. The exercise and heart evidence was built on men, so let your own response correct those numbers |
Exercise & recovery
| The source | What the book says it shows, and where |
|---|---|
| Thorogood et al., Am J Med 2011 (14 RCTs, n=1,847).Moderate | Aerobic exercise alone, −1.6 kg at six months in adults with overweight or obesity. The authors call it of limited value on its own, and note it may work combined with diet. Graded below its design class because that conclusion is conditional rather than settled.Used on page 39 Full citationThorogood et al. Isolated aerobic exercise and weight loss: a systematic review and meta-analysis of randomized controlled trials. Am J Med. 2011;124:747-55. doi:10.1016/j.amjmed.2011.02.037 · PMID 21787904 What the book does with itp39“And training is a weak weight tool: pooled trials find aerobic exercise alone takes off about 1.6 kg over six months, so the plate does the weight job and fitness carries the survival signal (Thorogood 2011; Lee 2011).” |
| Lee et al., Circulation 2011 (n=14,345 men).Moderate | Each 1-MET gain in fitness, 15% lower all-cause mortality. Change in weight showed no significant independent effect once fitness change was in the model. Prospective cohort.Used on page 39 Full citationLee et al. Long-term effects of changes in cardiorespiratory fitness and body mass index on all-cause and cardiovascular disease mortality in men: the Aerobics Center Longitudinal Study. Circulation. 2011;124:2483-90. doi:10.1161/CIRCULATIONAHA.111.038422 · PMID 22144631 What the book does with itp39“And training is a weak weight tool: pooled trials find aerobic exercise alone takes off about 1.6 kg over six months, so the plate does the weight job and fitness carries the survival signal (Thorogood 2011; Lee 2011).” |
| Xiao & Ren, Life 2025 (78 studies).Moderate | Once measurement error is modeled, no consistent evidence of true differences in trainability. Much of what looks like a non-responder may be measurement noise. A modeling review across heterogeneous studies rather than a pooling of randomized outcomes, so it is graded below its size.Used on pages 42, 56 Full citationXiao & Ren. Inter-Individual Heterogeneity in Aerobic Training Adaptations: Systematic Review of the Evidence Base for Personalized Exercise Prescription. Life (Basel). 2025;15. doi:10.3390/life15121932 · PMID 41465870 What the book does with itp42“Much of what looks like a non-responder may be noise (Xiao 2025; Bonafiglia 2021).” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can |
| Bonafiglia et al., Front Physiol 2021 (systematic review, 149 studies).Moderate | A review of methods rather than outcomes: few of the studies it examined separated true individual response from measurement error, and more lenient thresholds returned more responders. It is not a synthesis of randomized outcomes, so it is graded below its size.Used on pages 42, 56 Full citationBonafiglia et al. A Systematic Review Examining the Approaches Used to Estimate Interindividual Differences in Trainability and Classify Individual Responses to Exercise Training. Front Physiol. 2021;12:665044. doi:10.3389/fphys.2021.665044 · PMID 34819869 What the book does with itp42“Much of what looks like a non-responder may be noise (Xiao 2025; Bonafiglia 2021).” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can |
| Leong et al., Lancet 2015 (PURE, n=139,691).Moderate | Grip strength predicted mortality more strongly than systolic blood pressure. Prospective cohort.Used on page 41 Full citationLeong et al. Prognostic value of grip strength: findings from the Prospective Urban Rural Epidemiology (PURE) study. Lancet. 2015;386:266-73. doi:10.1016/S0140-6736(14)62000-6 · PMID 25982160 What the book does with itp41“Lower grip strength was associated with higher all-cause and cardiovascular mortality, and in that dataset it predicted death more strongly than systolic blood pressure did (Leong 2015).” And on page 41 the reader is told · How to use itGrip needs no lab, only a cheap hand dynamometer. Train the whole body, and let grip be the dial you read, a proxy for the whole |
| Shailendra et al., Am J Prev Med 2022 (meta of cohorts).Moderate | Resistance plus aerobic training tracked with lower mortality than either alone. Observational.Used on page 40 Full citationShailendra et al. Resistance Training and Mortality Risk: A Systematic Review and Meta-Analysis. Am J Prev Med. 2022;63:277-285. doi:10.1016/j.amepre.2022.03.020 · PMID 35599175 What the book does with itp40“Put resistance and aerobic training together and a separate pooling of the cohorts found the combination tracked with lower mortality than either on its own (Shailendra 2022).” And on page 40 the reader is told · How to use itThis is why the book asks for two lifting sessions and treats cardio as one part of fitness. For strength work specifically, the association was strongest at modest weekly volumes |
| Han et al., BJSM 2022.Moderate | Higher VO₂max tracked with lower mortality, in the same direction as the Mandsager entry below. Observational.Used on page 43 Full citationHan et al. Cardiorespiratory fitness and mortality from all causes, cardiovascular disease and cancer: dose-response meta-analysis of cohort studies. Br J Sports Med. 2022;56:733-739. doi:10.1136/bjsports-2021-104876 · PMID 35022163 What the book does with itp43Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Balachandran et al., JAMA Netw Open 2022 (20 RCTs, n=566, mean age 70).Moderate | Power training gave a modest edge over strength training for physical function. Small trials and the authors rated it low-certainty.Used on page 68 Full citationBalachandran et al. Comparison of Power Training vs Traditional Strength Training on Physical Function in Older Adults: A Systematic Review and Meta-analysis. JAMA Netw Open. 2022;5:e2211623. doi:10.1001/jamanetworkopen.2022.11623 · PMID 35544136 What the book does with itp68Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 68 the reader is told · The move on that pageExercise Three days a week rather than two: for over-65s the WHO guidelines ask for three or more, combining strength, balance and movement (Bull 2020). That means balance and strength on at least three days, the two lifting sessions with sit-to-stands and a carry among them, a walk, and something quick for power like standing up fast, a hand ready. |
| Roberts et al., J Physiol 2015 (RCT, n=21, 12 weeks).Moderate | Cold water immersion after lifting blunted long-term strength gains. One small trial, which on its own would sit at Emerging. The strength half is held one tier higher, at Moderate, because a later pooling of eight trials found the same direction (Malta 2021, PMID 33146851). That pooling gives only the direction here, while the hypertrophy half is the weaker of the two and pools to an interval crossing zero.Used on pages 45, 51 Full citationRoberts et al. Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training. J Physiol. 2015;593:4285-301. doi:10.1113/JP270570 · PMID 26174323 What the book does with itp45Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 45 the reader is told · Remember thisFive nights at four hours cut the muscle-building signal by about 19%, though an exercise arm in the same study held it normal p51Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Currier et al., ACSM Position Stand, Med Sci Sports Exerc 2026 (137 reviews, >30,000 people).Guidance | Branded a Position Stand, and by its own subtitle an overview of reviews rather than a consensus panel. Its headline finding is that few prescription variables affected the primary adaptations. Those that did: heavier loads, full range, 2 to 3 sets, twice a week and hard work early in the session for strength; higher weekly volume and eccentric overload for size; moderate loads of 30 to 70% of one-rep max moved fast for power. Training to failure, time under tension, equipment and periodization did not consistently matter.Used on pages 43, 46, 68 Full citationCurrier et al., ACSM Position Stand. American College of Sports Medicine Position Stand. Resistance Training Prescription for Muscle Function, Hypertrophy, and Physical Performance in Healthy Adults: An Overview of Reviews. Med Sci Sports Exerc. 2026;58:851-872. doi:10.1249/MSS.0000000000003897 · PMID 41843416 What the book does with itp46“How long the gap should be is training convention; the ACSM overview makes no recommendation on it (Currier 2026).” |
| Mandsager et al., JAMA Netw Open 2018 (retrospective, n=122,007).Moderate | Higher VO₂max, lower mortality, no ceiling: ~40% between below- and above-average fitness, roughly five-fold from least fit to the top 2%. Patients referred for testing, so confounding by indication is the caveat.Used on pages 39, 40, 42, 43 Full citationMandsager et al. Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing. JAMA Netw Open. 2018;1:e183605. doi:10.1001/jamanetworkopen.2018.3605 · PMID 30646252 What the book does with itp40“Between the least fit and the very fittest it was roughly five-fold, among patients referred for a treadmill test (Mandsager 2018).” p40“After a treadmill test, Mandsager and colleagues tracked 122,007 people for mortality.” And on page 40 the reader is told · How to use itThe curve keeps rising, but it is steepest at the bottom, so getting off the lowest rung buys the most. The easy base does that work, with one or two hard sessions to raise the top end p42“The fitness-and-mortality numbers are on page 40: 122,000 patients, no ceiling of benefit, roughly five-fold between the least and most fit (Mandsager 2018).” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can |
| Tudor-Locke & Bassett, Sports Med 2004 (review).Background | The 10,000-step figure traces to Japanese walking clubs and a business slogan. No trial behind it.Used on page 40 Full citationTudor-Locke & Bassett. How many steps/day are enough? Preliminary pedometer indices for public health. Sports Med. 2004;34:1-8. doi:10.2165/00007256-200434010-00001 · PMID 14715035 What the book does with itp40“It traces to Japanese walking clubs and a business slogan (Tudor-Locke 2004).” And on page 40 the reader is told · How to use itIf you are inactive and below 3,000, I would add 500 to 1,000 a day and hold it before chasing 7,000. Over 60, I would put the effort past that point into the lifting. Under 60 there are still steps worth adding past it |
| Ding et al., Lancet Public Health 2025.Moderate | ~47% lower all-cause mortality from 2,000 to 7,000 steps, then a plateau. Certainty moderate for most outcomes, low for several; the authors name the absence of an age-specific analysis as a limitation.Used on pages 10, 39, 40, 44 Full citationDing et al. Daily steps and health outcomes in adults: a systematic review and dose-response meta-analysis. Lancet Public Health. 2025;10:e668-e681. doi:10.1016/S2468-2667(25)00164-1 · PMID 40713949 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p40“Against the lowest step counts that is roughly 47% lower all-cause mortality, in observational data (Ding 2025).” p40“Pool the step-count studies, as Ding and colleagues did, and risk falls steeply from around 2,000 steps to about 7,000.” And on page 40 the reader is told · How to use itIf you are inactive and below 3,000, I would add 500 to 1,000 a day and hold it before chasing 7,000. Over 60, I would put the effort past that point into the lifting. Under 60 there are still steps worth adding past it |
| Paluch et al., Lancet Public Health 2022 (15 cohorts, n=47,471).Moderate | Where the plateau sits depends on age: risk kept falling to about 6,000 to 8,000 steps in adults 60 and over, and to about 8,000 to 10,000 under 60. The book’s age split comes from here. Pooled prospective cohorts, so an association.Used on pages 39, 40, 44 Full citationPaluch et al. Daily steps and all-cause mortality: a meta-analysis of 15 international cohorts. Lancet Public Health. 2022;7:e219-e228. doi:10.1016/S2468-2667(21)00302-9 · PMID 35247352 What the book does with itp40“Under 60 the leveling-off sits nearer 8,000 to 10,000 (Paluch 2022).” And on page 40 the reader is told · How to use itIf you are inactive and below 3,000, I would add 500 to 1,000 a day and hold it before chasing 7,000. Over 60, I would put the effort past that point into the lifting. Under 60 there are still steps worth adding past it |
| Sherrington et al., Cochrane 2019 (108 RCTs, n=23,407).Strong | Balance and functional exercise cut the rate of falls 24% against control (39 trials, n=7,920, high certainty). Several exercise types combined, usually balance plus resistance, cut it 34% (11 trials, n=1,374, moderate certainty). Both against control rather than each other; resistance alone is left uncertain.Used on pages 10, 41, 44, 68 Full citationSherrington et al. Exercise for preventing falls in older people living in the community. Cochrane Database Syst Rev. 2019;1:CD012424. doi:10.1002/14651858.CD012424.pub2 · PMID 30703272 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p41“Neither figure comes from testing one against the other (Sherrington 2019).” And on page 41 the reader is told · How to use itIt is why a two-minute daily habit that looks trivial has a place in a short book. Balance is one of the few qualities where training it directly is shown to work |
| NHIS 2020 (US National Health Interview Survey).Emerging | About 32% of adults did muscle-strengthening activity on two or more days a week. A national participation rate from a cross-sectional survey. No trial.Used on page 42 Full citationNational Center for Health Statistics, CDC. 2020 National Health Interview Survey (NHIS) Questionnaires, Datasets, and Documentation. cdc.gov/nchs/nhis/2020nhis.htm What the book does with itp42“About a third of adults train for strength twice a week, the level the guidelines ask for (NHIS 2020, US).” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can |
| Momma et al., BJSM 2022 (meta of cohorts).Moderate | Muscle-strengthening activity and lower mortality, strongest at modest volumes.Used on pages 10, 39, 40 Full citationMomma et al. Muscle-strengthening activities are associated with lower risk and mortality in major non-communicable diseases: a systematic review and meta-analysis of cohort studies. Br J Sports Med. 2022;56:755-763. doi:10.1136/bjsports-2021-105061 · PMID 35228201 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p40“The association was strongest at modest volumes and faded at high ones (Momma 2022).” p40“Momma and colleagues pooled the cohort evidence.” And on page 40 the reader is told · How to use itThis is why the book asks for two lifting sessions and treats cardio as one part of fitness. For strength work specifically, the association was strongest at modest weekly volumes |
| Bull et al., BJSM 2020 (WHO guidelines).Guidance | 150 to 300 minutes of moderate activity a week, plus strength on two days. Over 65, three or more days combining strength, balance and moving around.Used on pages 39, 68 Full citationBull et al. World Health Organization 2020 guidelines on physical activity and sedentary behaviour. Br J Sports Med. 2020;54:1451-1462. doi:10.1136/bjsports-2020-102955 · PMID 33239350 What the book does with itp39“The WHO target is 150 to 300 minutes of moderate cardio a week, at a pace where you can still hold a conversation.” p68“Exercise Three days a week rather than two: for over-65s the WHO guidelines ask for three or more, combining strength, balance and movement (Bull 2020).” And on page 68 the reader is told · The move on that pageExercise Three days a week rather than two: for over-65s the WHO guidelines ask for three or more, combining strength, balance and movement (Bull 2020). That means balance and strength on at least three days, the two lifting sessions with sit-to-stands and a carry among them, a walk, and something quick for power like standing up fast, a hand ready. |
| Buffey et al., Sports Med 2022 (meta of trials).Moderate | Light walks of two to five minutes blunt the glucose rise against staying seated. Acute crossovers, mostly in adults with overweight.Used on pages 44, 60 Full citationBuffey et al. The Acute Effects of Interrupting Prolonged Sitting Time in Adults with Standing and Light-Intensity Walking on Biomarkers of Cardiometabolic Health in Adults: A Systematic Review and Meta-analysis. Sports Med. 2022;52:1765-1787. doi:10.1007/s40279-022-01649-4 · PMID 35147898 What the book does with itp44“Breaking up sitting with two to five minutes of light walking blunts the glucose rise compared with staying seated (Buffey 2022).” |
| Saner et al., J Physiol 2020.Emerging | Five nights at four hours cut the muscle-building response ~19%. Three interval sessions across the same nights held it at control levels. Eight men per group.Used on pages 23, 24, 42, 45, 46 Full citationSaner et al. The effect of sleep restriction, with or without high-intensity interval exercise, on myofibrillar protein synthesis in healthy young men. J Physiol. 2020;598:1523-1536. doi:10.1113/JP278828 · PMID 32078168 What the book does with itp23“In an exercise arm across those same nights the drop did not appear (Saner 2020, three groups of eight young men).” And on page 23 the reader is told · Remember thisTraining buys minutes of deep sleep, and a nightcap costs you the rest of the night p42“Protein supplies the material (Morton 2018), recovery banks it (Saner 2020), and the training itself raises slow-wave sleep (Kredlow 2015).” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can p45“In one controlled study, five nights of short sleep cut the muscle-building response measured in muscle tissue by about 19% (Saner 2020).” And on page 45 the reader is told · Remember thisFive nights at four hours cut the muscle-building signal by about 19%, though an exercise arm in the same study held it normal |
| Stamatakis et al., Nat Med 2022 (n=25,241).Moderate | Brief vigorous daily bursts track with lower mortality, near-linear dose-response. Prospective cohort.Used on pages 39, 40 Full citationStamatakis et al. Association of wearable device-measured vigorous intermittent lifestyle physical activity with mortality. Nat Med. 2022;28:2521-2529. doi:10.1038/s41591-022-02100-x · PMID 36482104 What the book does with itp40“Brief daily bursts of this kind tracked with lower all-cause mortality and lower cardiovascular mortality, on a near-linear dose-response (Stamatakis 2022).” p40“25,241 people who never formally exercise: that was the sample Stamatakis studied.” And on page 40 the reader is told · How to use itCollect a few of these a day instead of counting minutes. A hard brisk walk is one way to get them; stairs at speed too, if you take them confidently |
| Koemel et al., Eur J Prev Cardiol 2025 (UK Biobank accelerometry, n=22,368 non-exercisers).Emerging | Four to five minutes a day of incidental vigorous bursts tracked with offsetting the cardiovascular risk of long sitting; at the no-burst end the estimate is compatible with no effect. One prospective cohort.Used on page 40 Full citationKoemel et al. Can incidental physical activity offset the deleterious associations of sedentary behaviour with major adverse cardiovascular events? Eur J Prev Cardiol. 2025;32:77-85. doi:10.1093/eurjpc/zwae316 · PMID 39325719 What the book does with itp40“The estimate at the no-burst end is compatible with no effect (Koemel 2025).” And on page 40 the reader is told · How to use itCollect a few of these a day instead of counting minutes. A hard brisk walk is one way to get them; stairs at speed too, if you take them confidently |
Data and support
| The source | What the book says it shows, and where |
|---|---|
| Manson et al., NEJM 2019 (VITAL, RCT, n=25,871, median 5.3 years).Established | 2,000 IU a day did not lower invasive cancer (HR 0.96) or major cardiovascular events (HR 0.97). Mean baseline vitamin D was already 30.8 ng/mL, so it is a null for supplementing replete people, and silent on correcting a measured deficiency.Used on page 51 Full citationManson et al. Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease. N Engl J Med. 2019;380:33-44. doi:10.1056/NEJMoa1809944 · PMID 30415629 Published online the year before its printed issue; the printed year is shown. What the book does with itp51“Vitamin D goes by the supplement guidance that applies to you (the allowances on page 29 are total intake rather than tablet doses) or by a low test, and a diagnosed deficiency has its own treatment plan; supplementing already-replete people moved neither main outcome over five years (Manson 2019).” |
| Abdelhamid et al., Cochrane 2020 (86 RCTs, n=162,796).Strong | Omega-3 supplements: all-cause mortality RR 0.97 on the 45 trials and 143,693 people that reported it, and cardiovascular events RR 0.96, both high certainty. A small reduction in coronary deaths is possible, low certainty.Used on page 51 Full citationAbdelhamid et al. Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database Syst Rev. 2020;3:CD003177. doi:10.1002/14651858.CD003177.pub5 · PMID 32114706 What the book does with itp51Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Kazeminasab et al., Nutrients 2025 (69 RCTs, n=1,937).Established | Squat +5.64 kg; the leg-press, women and over-50 subgroups were all null, so it is capped at Established rather than settling the direction for everyone. Larger and newer than Wang, and measuring the squat rather than a lower-body composite.Used on pages 39, 50, 51, 75 Full citationKazeminasab et al. The Effects of Creatine Supplementation on Upper- and Lower-Body Strength and Power: A Systematic Review and Meta-Analysis. Nutrients. 2025;17. doi:10.3390/nu17172748 · PMID 40944139 What the book does with itp50“Squat, Kazeminasab 2025, 69 trials ~+5.6 kg / 12 lb” p50“These are not two estimates of one number: Wang pooled a lower-body composite; the Kazeminasab bar is the squat specifically.” And on page 50 the reader is told · Remember thisChange one optional supplement at a time, cleared with a pharmacist. If nothing you can observe has moved in a couple of months, stop paying for it. That rule is for the extras, never for a preventive dose like folic acid or vitamin D, or anything a clinician told you to take p51“The larger pool found a smaller gain on the squat, and no clear effect in the smaller women and over-50 subgroups (Kazeminasab 2025).” p75“Kazeminasab 2025’s larger pool has over-50 and women subgroups, both null, while a seven-trial review in postmenopausal women found a leg-press gain of about 7.5 kg / 17 lb on three trials and 111 women (Naddafha 2026).” And on page 75 the reader is told · In shortThe pillars are the same across sexes and life stages; the transition years reward the same levers, adjusted to the stage. Iron splits by sex: often low in women who menstruate, building up in men who take it untested. Menopause protein protocols rest on thin evidence, and pregnancy changes what to leave alone |
| Antonio et al., J Int Soc Sports Nutr 2021 (review).Background | Creatine can raise serum creatinine without harming kidney function in healthy adults; the basis for telling whoever draws your blood. A narrative review answering common questions, so background. Full citationAntonio et al. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? J Int Soc Sports Nutr. 2021;18:13. doi:10.1186/s12970-021-00412-w · PMID 33557850 |
| Naddafha et al., J Int Soc Sports Nutr 2026 (7 RCTs, n=608 randomized, postmenopausal; 12 to 104 weeks, median 38).Moderate | Leg-press 1RM +7.5 kg (CI +2.2 to +12.8) on 3 of the 7 trials and 111 women. Lean mass +0.37 kg (CI +0.05 to +0.69) on 5 trials and 338 women, though the prediction interval crosses zero. Bone density unchanged. Only at 5 g a day with lifting. It pooled postmenopausal trials, where the larger review reports a null subgroup, so the two disagree on the size of the gain.Used on page 75 Full citationNaddafha et al. Creatine monohydrate for lean mass, strength, and bone density in postmenopausal women: a systematic review and meta-analysis. J Int Soc Sports Nutr. 2026;23:2668435. doi:10.1080/15502783.2026.2668435 · PMID 42141930 What the book does with itp75“Kazeminasab 2025’s larger pool has over-50 and women subgroups, both null, while a seven-trial review in postmenopausal women found a leg-press gain of about 7.5 kg / 17 lb on three trials and 111 women (Naddafha 2026).” And on page 75 the reader is told · In shortThe pillars are the same across sexes and life stages; the transition years reward the same levers, adjusted to the stage. Iron splits by sex: often low in women who menstruate, building up in men who take it untested. Menopause protein protocols rest on thin evidence, and pregnancy changes what to leave alone |
| NIH Office of Dietary Supplements fact sheets.Guidance | The micronutrient upper limits the book prints, and the basis for testing ferritin before supplementing iron, since excess iron accumulates instead of clearing.Used on pages 18, 29, 34, 51, 73, 74 Full citationNIH Office of Dietary Supplements. Dietary Supplement Fact Sheets. ods.od.nih.gov/factsheets/list-all What the book does with itp73“In men, low iron is uncommon and needs its cause found, and untested supplementing can do harm (NIH ODS; BSG 2021).” And on page 73 the reader is told · In shortThe differences are mostly timing and weighting. The exercise and heart evidence was built on men, so let your own response correct those numbers p74“In men the risk runs the other way, since excess iron accumulates and causes harm (NIH Office of Dietary Supplements).” And on page 74 the reader is told · What to do about itTest first. If you menstruate and are tired in a way sleep does not fix, ask to be assessed before buying anything, and let whoever ordered the test decide what to correct. A man taking iron without a test that says he needs it should ask before the next course |
| Liao et al., Eur J Med Res 2026 (systematic review).Moderate | Continuous glucose monitoring showed no glycemic benefit in normoglycemic people; the benefit was confined to prediabetes.Used on pages 48, 66 Full citationLiao et al. Continuous glucose monitoring in non-diabetic populations: a systematic review of observational and interventional studies with meta-analysis. Eur J Med Res. 2026. doi:10.1186/s40001-026-03920-0 · PMID 41588451 What the book does with itp48“A continuous glucose monitor in someone with normal blood sugar seldom changes the plan, and a review of the trials found no glycemic benefit at normal glucose (Liao 2026).” And on page 48 the reader is told · Remember thisMost of these move with the three pillars. Lp(a) is inherited, and the guideline has it measured once in adulthood |
| Zhang, Shen & Qi, CMAJ 2016 (meta of 46 cohorts, n=1,246,203).Moderate | Each 10 beats a minute higher resting heart rate carried about 9% higher all-cause mortality. Pooled prospective cohorts, all clinic-measured, with heterogeneity and publication bias reported by the authors.Used on page 49 Full citationZhang, Shen & Qi. Resting heart rate and all-cause and cardiovascular mortality in the general population: a meta-analysis. CMAJ. 2016;188:E53-E63. doi:10.1503/cmaj.150535 · PMID 26598376 Published online the year before its printed issue; the printed year is shown. What the book does with itp49“The heart-rate evidence is clinic-measured, about 9% more risk per 10 beats a minute across 46 cohorts (Zhang 2016); whether a wrist estimate carries the same signal is open.” |
| Plews et al., Sports Med 2013 (narrative review).Emerging | HRV read against your own baseline rather than a norm. Derived from elite endurance athletes managing training load, never from health outcomes.Used on page 49 Full citationPlews et al. Training adaptation and heart rate variability in elite endurance athletes: opening the door to effective monitoring. Sports Med. 2013;43:773-81. doi:10.1007/s40279-013-0071-8 · PMID 23852425 What the book does with itp49Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Kravitz & Duan (AHRQ) 2014.Background | N-of-1 trial methods guide. A methods authority. Not itself a study.Used on page 56 Full citationKravitz RL, Duan N (eds); AHRQ. Design and Implementation of N-of-1 Trials: A User’s Guide (AHRQ Publication No. 13(14)-EHC122-EF). 2014. effectivehealthcare.ahrq.gov/products/n-1-trials/research-2014-5 What the book does with itp56“The formal version is the n-of-1 trial, recognized as legitimate evidence for one person’s decisions (AHRQ n-of-1 guide, Kravitz & Duan 2014).” And on page 56 the reader is told · How to use itKeep the plate advice as your default; use n-of-1 for low-risk habits such as a wind-down. Never run a food challenge on yourself: a possible allergic reaction or unexplained symptoms go to a clinician first (NHS) |
| Welch, Schwartz & Woloshin, Overdiagnosed, 2011.Background | Overtesting harms. Background reading. Not itself a study.Used on pages 49, 66 Full citationWelch HG, Schwartz LM, Woloshin S. Overdiagnosed: Making People Sick in the Pursuit of Health (Boston: Beacon Press). 2011. wellcomecollection.org/works/y47a8ekm What the book does with itp49Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. p66Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 66 the reader is told · The move on that pageExercise A VO₂max estimate or a simple fitness proxy is the number worth raising. Wearable estimates carry real error, so watch the trend. |
| ACC/AHA and nine other societies, JACC 2026 (dyslipidemia guideline).Guidance | Retires and replaces the 2018 cholesterol guideline. Lp(a) once in adulthood, with repeat testing generally not needed because lifestyle barely moves it. ApoB refines risk in selected people, most clearly with high triglycerides, diabetes or an already low LDL, rather than on every panel.Used on page 48 Full citationACC/AHA and nine other societies (Blumenthal et al.). 2026 ACC/AHA/AACVPR/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA Guideline on the Management of Dyslipidemia: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. J Am Coll Cardiol. 2026;87:2624-2757. doi:10.1016/j.jacc.2025.11.016 · PMID 41824590 What the book does with itp48“Measure once in adulthood: lifestyle barely moves it, so repeat testing is generally not needed (ACC/AHA 2026).” And on page 48 the reader is told · Remember thisMost of these move with the three pillars. Lp(a) is inherited, and the guideline has it measured once in adulthood |
| USPSTF 2021 (JAMA, Grade B); MOH Singapore, Screen for Life.Guidance | USPSTF: screen for prediabetes and type 2 diabetes at ages 35 to 70 in people with overweight or obesity, earlier and at a lower BMI in higher-risk groups, every three years when the result is normal. MOH: from 40, every three years, younger with risk factors. Gated by age and risk; three years is the guidance interval for a normal result.Used on page 49 Full citationUS Preventive Services Task Force (Davidson et al.). Screening for Prediabetes and Type 2 Diabetes: US Preventive Services Task Force Recommendation Statement. JAMA. 2021;326:736-743. doi:10.1001/jama.2021.12531 · PMID 34427594 Ministry of Health Singapore / Health Promotion Board. Screen for Life - National Health Screening Programme (now titled Healthier SG Screening). healthhub.sg/programmes/screen_for_life What the book does with itp49“Both call every three years reasonable when the result is normal (USPSTF 2021; MOH).” p49“For diabetes, USPSTF screens adults 35 to 70 with overweight or obesity, sooner and at a lower weight for Asian Americans and other higher-risk groups; Singapore screens everyone from 40.” |
| AHA/ATVB scientific statement 2022.Guidance | Lp(a) is 70 to 90% inherited and high in roughly one in five people, more often in African ancestry and less often in East Asian. Measure at least once. The 2026 guideline says repeat testing is generally not needed, because lifestyle barely moves it.Used on pages 48, 49, 66 Full citationReyes-Soffer et al. (AHA scientific statement). Lipoprotein(a): A Genetically Determined, Causal, and Prevalent Risk Factor for Atherosclerotic Cardiovascular Disease: A Scientific Statement From the American Heart Association. Arterioscler Thromb Vasc Biol. 2022;42:e48-e60. doi:10.1161/ATV.0000000000000147 · PMID 34647487 What the book does with itp48“Largely genetic, and high in roughly one person in five (AHA/ATVB 2022).” And on page 48 the reader is told · Remember thisMost of these move with the three pillars. Lp(a) is inherited, and the guideline has it measured once in adulthood |
| Lopez-Jaramillo et al., Lancet Healthy Longev 2023 (PURE, n=141,243).Moderate | TyG flags insulin resistance from a standard panel.Used on pages 48, 49 Full citationLopez-Jaramillo et al. Association of the triglyceride glucose index as a measure of insulin resistance with mortality and cardiovascular disease in populations from five continents (PURE study): a prospective cohort study. Lancet Healthy Longev. 2023;4:e23-e33. doi:10.1016/S2666-7568(22)00247-1 · PMID 36521498 Published online the year before its printed issue; the printed year is shown. What the book does with itp48“The triglyceride-glucose (TyG) index is computable from a standard fasting panel and flags insulin resistance, and it is not in the table above because no guideline I found uses it and published cutoffs disagree (Lopez-Jaramillo 2023).” And on page 48 the reader is told · Remember thisMost of these move with the three pillars. Lp(a) is inherited, and the guideline has it measured once in adulthood |
| Halonen et al., Scand J Med Sci Sports 2024 (RCT, n=55, untrained adults).Emerging | After a ten-week break, lost strength and size came back within the first five weeks of retraining, and the groups ended level. One trial in the untrained; no individual recovery time or mechanism.Used on page 42 Full citationHalonen EJ, Gabriel I, Kelahaara MM, Ahtiainen JP, Hulmi JJ. Does Taking a Break Matter-Adaptations in Muscle Strength and Size Between Continuous and Periodic Resistance Training. Scand J Med Sci Sports. 2024;34:e14739. doi:10.1111/sms.14739 · PMID 39364857 What the book does with itp42“One trial in previously untrained adults found lost strength and muscle size came back quickly during retraining (Halonen 2024); it does not predict your recovery time or settle the mechanism.” And on page 42 the reader is told · Remember thisOn a bad month, keep one short set and two minutes of balance beside a counter, and a walk if you can |
| Wang et al., Nutrients 2024 (23 RCTs, adults under 50).Established | Creatine plus training adds strength: lower body +11.35 kg, upper body +4.43 kg. Almost all male, and the female subgroup was too small to settle anything either way, so it is capped at Established.Used on pages 39, 50, 51, 75 Full citationWang et al. Effects of Creatine Supplementation and Resistance Training on Muscle Strength Gains in Adults <50 Years of Age: A Systematic Review and Meta-Analysis. Nutrients. 2024;16. doi:10.3390/nu16213665 · PMID 39519498 What the book does with itp50“Lower body, Wang 2024, 23 trials +11.4 kg / 25 lb” p50“Upper body, Wang 2024 +4.4 kg / 10 lb” And on page 50 the reader is told · Remember thisChange one optional supplement at a time, cleared with a pharmacist. If nothing you can observe has moved in a couple of months, stop paying for it. That rule is for the extras, never for a preventive dose like folic acid or vitamin D, or anything a clinician told you to take p51“The trials enrolled almost only men under 50 (Wang 2024).” p75“Wang 2024’s 23 trials were almost all male and under 50.” And on page 75 the reader is told · In shortThe pillars are the same across sexes and life stages; the transition years reward the same levers, adjusted to the stage. Iron splits by sex: often low in women who menstruate, building up in men who take it untested. Menopause protein protocols rest on thin evidence, and pregnancy changes what to leave alone |
| Laukkanen et al., JAMA Intern Med 2015 (cohort).Moderate | Sauna use and lower mortality. An observational cohort of Finnish men, healthy-user bias not excluded; the group’s later cohorts include women.Used on page 51 Full citationLaukkanen et al. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Intern Med. 2015;175:542-8. doi:10.1001/jamainternmed.2014.8187 · PMID 25705824 What the book does with itp51Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| Lee et al., Am J Physiol Regul Integr Comp Physiol 2022 (three-arm RCT, n=47, 8 weeks).Emerging | Exercise plus a 15-minute post-exercise sauna improved blood pressure, fitness and cholesterol against exercise alone. Surrogate markers, no sauna-only arm, no mortality.Used on pages 50, 51 Full citationLee et al. Effects of regular sauna bathing in conjunction with exercise on cardiovascular function: a multi-arm, randomized controlled trial. Am J Physiol Regul Integr Comp Physiol. 2022;323:R289-R299. doi:10.1152/ajpregu.00076.2022 · PMID 35785965 What the book does with itp50“Exercise plus sauna over eight weeks in 47 adults improved blood pressure, fitness and cholesterol (Lee 2022).” And on page 50 the reader is told · Remember thisChange one optional supplement at a time, cleared with a pharmacist. If nothing you can observe has moved in a couple of months, stop paying for it. That rule is for the extras, never for a preventive dose like folic acid or vitamin D, or anything a clinician told you to take |
| Sesso et al., Am J Clin Nutr 2022 (COSMOS, n=21,442).Established | A daily multivitamin gave no benefit on cancer, cardiovascular disease or mortality in the already-fed. The linked cognition reports rest on a different endpoint, which the book does not use.Used on page 51 Full citationSesso et al. Multivitamins in the prevention of cancer and cardiovascular disease: the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial. Am J Clin Nutr. 2022;115:1501-1510. doi:10.1093/ajcn/nqac056 · PMID 35294969 What the book does with itp51Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
Guidance and formularies
| The source | What the book says it shows, and where |
|---|---|
| NIH Office of Dietary Supplements, magnesium fact sheet for health professionals.Guidance | Magnesium toxicity risk rises when the kidneys, which clear it, are impaired; upper limit 350 mg a day from supplements. The basis for the kidney caution; the clinician’s-call framing is the book’s.Used on pages 18, 29, 34, 51, 73, 74 Full citationNIH Office of Dietary Supplements. Magnesium: Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/Magnesium-HealthProfessional What the book does with itp73“In men, low iron is uncommon and needs its cause found, and untested supplementing can do harm (NIH ODS; BSG 2021).” And on page 73 the reader is told · In shortThe differences are mostly timing and weighting. The exercise and heart evidence was built on men, so let your own response correct those numbers p74“In men the risk runs the other way, since excess iron accumulates and causes harm (NIH Office of Dietary Supplements).” And on page 74 the reader is told · What to do about itTest first. If you menstruate and are tired in a way sleep does not fix, ask to be assessed before buying anything, and let whoever ordered the test decide what to correct. A man taking iron without a test that says he needs it should ask before the next course |
| AASM restless legs guideline, J Clin Sleep Med 2025 (Winkelman).Guidance | Check ferritin in clinically significant restless legs; treat iron at a much higher threshold than for anemia. A consensus statement with no trial-derived cutoff.Used on page 72 Full citationWinkelman et al. (AASM clinical practice guideline). Treatment of restless legs syndrome and periodic limb movement disorder: an American Academy of Sleep Medicine clinical practice guideline. J Clin Sleep Med. 2025;21:137-152. doi:10.5664/jcsm.11390 · PMID 39324694 What the book does with itp72“Thresholds follow WHO criteria, NICE NG136 and NG133, and the AASM; stroke signs, the NHS; muscle signs, the CDC.” And on page 72 the reader is told · In shortThresholds follow WHO criteria, NICE NG136 and NG133, and the AASM; stroke signs, the NHS; muscle signs, the CDC. One reading is rarely a diagnosis |
| WHO sodium guideline 2012; SACN 2003 (UK); Dietary Guidelines for Americans.Guidance | Under 5 g of salt a day (WHO), 6 g (UK), or under 2,300 mg of sodium (US, 2025 edition). The book prints the 5 to 6 g salt range they translate to; the DGA food-sources table supplies the fiber card’s portion figures.Used on page 34 Full citationWorld Health Organization. Guideline: Sodium intake for adults and children. 2012. who.int/publications/i/item/9789241504836 Scientific Advisory Committee on Nutrition (UK). Salt and Health. 2003. gov.uk/government/publications/sacn-salt-and-health-report US Department of Agriculture and US Department of Health and Human Services. Dietary Guidelines for Americans. dietaryguidelines.gov What the book does with itp34Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| SACN, Vitamin D and Health, 2016; NHS; HealthHub (HPB), Singapore.Guidance | The UK figure is a 10 µg supplement in autumn and winter, year-round with little sun; upper limit 100 µg (4,000 IU). Singapore’s 2.5 µg a day is HPB’s adult dietary allowance for total intake (HealthHub RDA page); the US 15 µg is a dietary allowance for total intake (NIH ODS).Used on pages 29, 34 Full citationScientific Advisory Committee on Nutrition (UK). Vitamin D and Health. 2016. gov.uk/government/publications/sacn-vitamin-d-and-health-report NHS (UK). Vitamin D - Vitamins and minerals. nhs.uk/conditions/vitamins-and-minerals/vitamin-d HealthHub (Ministry of Health Singapore / Health Promotion Board). Recommended dietary allowances. The entry names no single document, so nothing is linked. What the book does with itp29Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. p34Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. |
| AAP 2022 safe sleep policy; HealthHub (HPB), Singapore.Guidance | Back for every sleep until a year old, on a firm flat surface with no incline, nothing loose in the crib, in the parents’ room but not their bed for at least six months. The NHS takes a harm-reduction line instead, so the page says whose rule it follows.Used on page 69 Full citationMoon et al. (AAP Task Force on Sudden Infant Death Syndrome). Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment. Pediatrics. 2022;150:e2022057990. doi:10.1542/peds.2022-057990 · PMID 35726558 Moon RY et al. Evidence Base for 2022 Updated Recommendations for a Safe Infant Sleeping Environment to Reduce the Risk of Sleep-Related Infant Deaths. Pediatrics. 2022;150:e2022057991. doi:10.1542/peds.2022-057991 · PMID 35921639 Health Promotion Board (HealthHub), Singapore. Q&A: How Can I Get My Baby to Sleep Well and Safely? healthhub.sg/well-being-and-lifestyle/pregnancy-and-infant-health/how-can-i-get-my-baby-to-sleep-well-and-safely What the book does with itp69“That is the Singapore and US guidance; the AAP does not recommend bed-sharing.” And on page 69 the reader is told · The move on that pageSleep On their back for every sleep until a year old; once they roll both ways, no need to turn them back, and stop swaddling at the first sign of trying to roll. Use a firm, flat surface with no incline, in their own clear crib, in your room but not your bed, for at least six months; no weighted swaddles, blankets or sleep products. That is the Singapore and US guidance; the AAP does not recommend bed-sharing. Never sleep with the baby on a sofa or an armchair, and never put the baby to sleep there; if you might drop off while feeding, use a bed cleared of pillows and bedding, and return the baby to the crib as soon as you wake. |
| NHS (foods to avoid in pregnancy; vitamins, supplements and nutrition in pregnancy), NICE NG201 (antenatal care) and NG247 (maternal nutrition, 2025).Guidance | Caffeine under 200 mg a day (NHS), cleared far more slowly late in pregnancy; no cod liver oil or retinol supplements, no liver (NHS); unpasteurized milk out, hard cheese fine, mold-ripened soft and soft blue cheese only cooked until steaming hot. Folic acid at the routine dose from before conception to week 12; 5 mg on prescription at higher risk (NG247). Full citationNational Institute for Health and Care Excellence (NICE). Antenatal care (NICE guideline NG201). 2021. nice.org.uk/guidance/ng201 National Institute for Health and Care Excellence (NICE). Maternal and child nutrition: nutrition and weight management in pregnancy, and nutrition in children up to 5 years (NICE guideline NG247). 2025. nice.org.uk/guidance/ng247 NHS. Have a healthy diet in pregnancy. nhs.uk/pregnancy/keeping-well/have-a-healthy-diet NHS. Foods to avoid in pregnancy. nhs.uk/pregnancy/keeping-well/foods-to-avoid NHS. Vitamins, supplements and nutrition in pregnancy. nhs.uk/pregnancy/keeping-well/vitamins-supplements-and-nutrition |
| EFSA, caffeine scientific opinion, 2015.Guidance | Up to 400 mg a day for adults, and 200 mg in pregnancy.Used on page 13 Full citationEFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Scientific Opinion on the safety of caffeine. 2015. doi:10.2903/j.efsa.2015.4102 What the book does with itp13“Up to about 400 mg a day is the level EFSA treats as safe rather than a target, and under 200 mg in pregnancy.” And on page 13 the reader is told · In shortCheck off enough sleep at a regular time, eat better, and start moving. Ask your clinician how these apply if you take a regular medicine, are pregnant, or have a diagnosed condition |
| NICE NG133 (hypertension in pregnancy).Guidance | 140/90 or above: secondary-care assessment; over 160/110: severe, admit; pre-eclampsia symptoms: immediate review. Both are on the warning-signs page.Used on page 72 Full citationNational Institute for Health and Care Excellence (NICE). Hypertension in pregnancy: diagnosis and management (NICE guideline NG133). 2019. nice.org.uk/guidance/ng133 What the book does with itp72“Pregnant or in the weeks after birth: severe headache, visual change, pain below the ribs or feeling very unwell: go in now, before measuring anything (NG133)” p72“Pregnant, and a reading of 140/90 mmHg or above, either number: call your maternity unit; over 160/110, either number: go in now (NG133)” And on page 72 the reader is told · In shortThresholds follow WHO criteria, NICE NG136 and NG133, and the AASM; stroke signs, the NHS; muscle signs, the CDC. One reading is rarely a diagnosis |
| NICE HTG624, formerly MTG70 (2022).Guidance | A digital CBT-I product assessed for NHS use in adults with insomnia.Used on page 21 Full citationNational Institute for Health and Care Excellence (NICE). Sleepio to treat insomnia and insomnia symptoms (NICE HealthTech guidance HTG624, formerly MTG70). 2022. nice.org.uk/guidance/htg624 What the book does with itp21“One automated self-help course has been assessed by NICE for NHS use in adults with insomnia (HTG624).” And on page 21 the reader is told · The one to keepHold the wake time within about half an hour on the days the night was long enough (a convention). After a short night, the extra sleep comes first; it is the sleeping in without a deficit that drifts the clock |
| DVLA, Assessing Fitness to Drive (UK, current edition); NHS zopiclone page; MHRA zolpidem drug safety update.Guidance | No driving while sleepiness is uncontrolled; notification rules differ by country. The leaflet’s minimum interval after a sleep-medicine dose applies: 12 hours for zopiclone (NHS), at least 8 for zolpidem (MHRA). Full citationDriver and Vehicle Licensing Agency (DVLA). Assessing fitness to drive: a guide for medical professionals. gov.uk/guidance/assessing-fitness-to-drive-a-guide-for-medical-professionals NHS. Zopiclone. nhs.uk/medicines/zopiclone MHRA. Zolpidem: risk of drowsiness and reduced driving ability (Drug Safety Update). gov.uk/drug-safety-update/zolpidem-risk-of-drowsiness-and-reduced-driving-ability |
| NHS: fit after a baby; postpartum psychosis; stroke; celiac; food allergy; the vegan diet; Crohn’s disease; diverticular disease; promethazine; diphenhydramine. CDC: maternal warning signs; rhabdomyolysis.Guidance | Routing after birth, CDC window a year; stroke signs; gluten until the celiac test; allergy assessed, never re-tested at home; B12 from fortified foods or a supplement on a vegan diet; the gut-condition rows (no big diet change without the team; the diverticular red flags); antihistamines a week (promethazine) or two (diphenhydramine); rhabdomyolysis on any one of severe pain, weakness or dark urine. Full citationNHS. Keeping fit and healthy with a baby. nhs.uk/baby/support-and-services/keeping-fit-and-healthy-with-a-baby NHS. Postpartum psychosis. nhs.uk/mental-health/conditions/post-partum-psychosis NHS. Symptoms of a stroke. nhs.uk/conditions/stroke/symptoms NHS. Coeliac disease: diagnosis. nhs.uk/conditions/coeliac-disease/diagnosis NHS. Food allergy. nhs.uk/conditions/food-allergy NHS. The vegan diet. nhs.uk/live-well/eat-well/how-to-eat-a-balanced-diet/the-vegan-diet NHS. Promethazine: how and when to take it. nhs.uk/medicines/promethazine/how-and-when-to-take-promethazine NHS. About diphenhydramine. nhs.uk/medicines/diphenhydramine/about-diphenhydramine Centers for Disease Control and Prevention (CDC). Urgent maternal warning signs (Hear Her). cdc.gov/hearher/maternal-warning-signs/index.html CDC/NIOSH. Signs and symptoms of rhabdomyolysis. cdc.gov/niosh/rhabdo/signs-symptoms/index.html NHS. Diverticular disease and diverticulitis. nhs.uk/conditions/diverticular-disease-and-diverticulitis NHS. Crohn’s disease. nhs.uk/conditions/crohns-disease |
| Testogel SmPC (electronic Medicines Compendium).Guidance | More sleep apnea reported in men on testosterone, most with obesity. Full citationBesins Healthcare (UK) Ltd, via electronic Medicines Compendium (emc). Testogel 16.2mg/g gel - Summary of Product Characteristics (SmPC). medicines.org.uk/emc/product/8919/smpc |
| WHO Housing and Health Guidelines, 2018.Guidance | 18°C as a minimum indoor temperature rather than a sleep target. Full citationWorld Health Organization. WHO Housing and health guidelines. 2018. who.int/publications/i/item/9789241550376 |
| NICE NG136 (hypertension in adults).Guidance | Its 180/120 pathway: same-day referral with signs or symptoms; otherwise organ-damage checks as soon as possible and a repeat within a week. Same day without symptoms is the book’s broader rule; the emergency line is the NHS’s; home 135/85 is stage 1.Used on page 72 Full citationNational Institute for Health and Care Excellence (NICE). Hypertension in adults: diagnosis and management (NICE guideline NG136). 2019. nice.org.uk/guidance/ng136 What the book does with itp72“Thresholds follow WHO criteria, NICE NG136 and NG133, and the AASM; stroke signs, the NHS; muscle signs, the CDC.” And on page 72 the reader is told · In shortThresholds follow WHO criteria, NICE NG136 and NG133, and the AASM; stroke signs, the NHS; muscle signs, the CDC. One reading is rarely a diagnosis |
| NICE CG100 and CG115 (alcohol-use disorders).Guidance | Withdrawal in a dependent drinker can cause seizures: the stopping-abruptly caution. Full citationNational Institute for Health and Care Excellence (NICE). Alcohol-use disorders: diagnosis and management of physical complications (NICE clinical guideline CG100). 2010. nice.org.uk/guidance/cg100 National Institute for Health and Care Excellence (NICE). Alcohol-use disorders: diagnosis, assessment and management of harmful drinking (high-risk drinking) and alcohol dependence (NICE clinical guideline CG115). 2011. nice.org.uk/guidance/cg115 |
| NICE NG238 (lipid modification); NHS statin advice.Guidance | Muscle symptoms on a statin: a question for the doctor, never a reason to stop on your own.Used on page 45 Full citationNational Institute for Health and Care Excellence (NICE). Cardiovascular disease: risk assessment and reduction, including lipid modification (NICE guideline NG238). 2023. nice.org.uk/guidance/ng238 NHS. Statins. nhs.uk/medicines/statins What the book does with itp45“Which tests to run is their call, and NICE NG238 sets out what a statin review covers.” And on page 45 the reader is told · Remember thisFive nights at four hours cut the muscle-building signal by about 19%, though an exercise arm in the same study held it normal |
| NICE NG206 (ME/CFS, 2021).Guidance | Post-exertional symptom worsening: stop progressing, cut back to what is tolerated, rest, and get assessed. Used here only as the stop rule on progression. Full citationNational Institute for Health and Care Excellence (NICE). Myalgic encephalomyelitis (or encephalopathy)/chronic fatigue syndrome: diagnosis and management (NG206). nice.org.uk/guidance/ng206 |
| Edinger et al., J Clin Sleep Med 2021 (AASM guideline).Guidance | CBT-I for chronic insomnia; sleep restriction alone, conditional.Used on page 21 Full citationEdinger et al. Behavioral and psychological treatments for chronic insomnia disorder in adults: an American Academy of Sleep Medicine clinical practice guideline. J Clin Sleep Med. 2021;17:255-262. doi:10.5664/jcsm.8986 · PMID 33164742 What the book does with itp21“The American College of Physicians and the sleep academy put it ahead of medication (Qaseem 2016; Edinger 2021).” And on page 21 the reader is told · The one to keepHold the wake time within about half an hour on the days the night was long enough (a convention). After a short night, the extra sleep comes first; it is the sleeping in without a deficit that drifts the clock |
| Snook et al., Gut 2021 (BSG iron deficiency guideline).Guidance | About a third of men and postmenopausal women with iron deficiency anemia have an underlying cause, most often in the gut. Full citationSnook et al. British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults. Gut. 2021;70:2030-2051. doi:10.1136/gutjnl-2021-325210 · PMID 34497146 |
| NICE NG246 (overweight and obesity management).Guidance | Waist-to-height under 0.5, replacing a single waist figure.Used on page 14 Full citationNational Institute for Health and Care Excellence (NICE). Overweight and obesity management (NICE guideline NG246). 2025. nice.org.uk/guidance/ng246 What the book does with itp14Named on the sources line of this page; the sentence built on it is the claim in the left column, and the page carries no other prose mention. And on page 14 the reader is told · In shortFIRST, THOUGH Four things to do before you optimize anything. None gets a chapter here, because none of them is what this book is about: (1) not smoking, (2) keeping your blood pressure treated, (3) taking the screening you are offered, and (4) your vaccinations. |
| BMS and Women’s Health Concern 2020 recommendations on HRT (Hamoda 2020); WHI extended follow-up, Manson 2013 and 2017.Guidance | The timing window, HRT started before 60 or within ten years of menopause, is the BMS document’s; the WHI follow-ups by age group are the revision of the original 2002 reading that the hormone-therapy row refers to.Used on pages 71, 75 Full citationBritish Menopause Society and Women’s Health Concern. BMS & WHC’s 2020 recommendations on hormone replacement therapy in menopausal women (consensus statement). thebms.org.uk/wp-content/uploads/2025/09/02-BMS-ConsensusStatement-BMS-WHC-2020-Recommendations-on-HRT-in-menopausal-women-SEPT2025-A.pdf Hamoda H, Panay N, Pedder H, Arya R, Savvas M. The British Menopause Society & Women’s Health Concern 2020 recommendations on hormone replacement therapy in menopausal women. Post Reprod Health. 2020;26:181-209. doi:10.1177/2053369120957514 · PMID 33045914 Manson JE et al. Menopausal hormone therapy and health outcomes during the intervention and extended poststopping phases of the Women’s Health Initiative randomized trials. JAMA. 2013;310:1353-68. doi:10.1001/jama.2013.278040 · PMID 24084921 Manson JE et al. Menopausal Hormone Therapy and Long-term All-Cause and Cause-Specific Mortality: The Women’s Health Initiative Randomized Trials. JAMA. 2017;318:927-938. doi:10.1001/jama.2017.11217 · PMID 28898378 What the book does with itp71“Worth knowing that the risk picture for HRT was revised after the original WHI reporting (Manson 2013, 2017), and the 2020 recommendations of the British Menopause Society set out the risk-benefit for healthy women under 60 starting within ten years of menopause (BMS 2020).” |
| WHO diabetes diagnostic criteria (2006; HbA1c report 2011); NICE NG28; MHRA drug safety updates; the gliflozin, sulfonylurea and insulin labels.Guidance | The diagnostic thresholds on the warning-signs page are WHO’s: fasting glucose reaching 7 mmol/L (126 mg/dL) and HbA1c reaching 48 mmol/mol (6.5%). Metformin and B12 is the MHRA’s 2022 update; gliflozin ketoacidosis the 2016 update and the labels; low blood sugar, the sulfonylurea and insulin labels. Full citationWorld Health Organization / International Diabetes Federation. Definition and diagnosis of diabetes mellitus and intermediate hyperglycaemia: report of a WHO/IDF consultation. 2006. iris.who.int/handle/10665/43588 World Health Organization. Use of glycated haemoglobin (HbA1c) in the diagnosis of diabetes mellitus: abbreviated report of a WHO consultation. 2011. who.int/publications/i/item/use-of-glycated-haemoglobin-(-hba1c)-in-diagnosis-of-diabetes-mellitus National Institute for Health and Care Excellence (NICE). Type 2 diabetes in adults: management (NICE guideline NG28). 2015. nice.org.uk/guidance/ng28 MHRA. Metformin and reduced vitamin B12 levels: new advice for monitoring patients at risk (Drug Safety Update, 20 June 2022). gov.uk/drug-safety-update/metformin-and-reduced-vitamin-b12-levels-new-advice-for-monitoring-patients-at-risk MHRA. SGLT2 inhibitors: updated advice on the risk of diabetic ketoacidosis (Drug Safety Update, 18 April 2016). gov.uk/drug-safety-update/sglt2-inhibitors-updated-advice-on-the-risk-of-diabetic-ketoacidosis NHS. Low blood sugar (hypoglycaemia). nhs.uk/conditions/low-blood-sugar-hypoglycaemia |
| Electronic Medicines Compendium SmPCs: ciprofloxacin, doxycycline, Losec (omeprazole), levothyroxine, Fosamax (alendronic acid).Guidance | The absorption interactions on the plate page, each from the product’s own SmPC: ciprofloxacin and doxycycline 4.5 (minerals, and the gap); Losec 4.4 (magnesium after three months; B12); levothyroxine 4.5 (proton pump inhibitors; iron and calcium, a 4 to 5 hour gap); Fosamax 4.2 (30 minutes before anything else). Full citationelectronic Medicines Compendium. Summaries of Product Characteristics (five products, in also). medicines.org.uk/emc Sun Pharma UK. Ciprofloxacin 500 mg film-coated tablets SmPC (revised 2 April 2026). medicines.org.uk/emc/product/4346/smpc Waymade (Sovereign Medical). Doxycycline 100mg Capsules SmPC (revised 17 March 2026). medicines.org.uk/emc/product/13082/smpc emc (marketing authorisation holder not recorded). Losec Capsules 20mg SmPC (revised 12 February 2026). medicines.org.uk/emc/product/1509/smpc Glenmark. Levothyroxine 50 micrograms Tablets SmPC (revised 2 July 2025). medicines.org.uk/emc/product/12780/smpc emc (marketing authorisation holder not recorded). Fosamax Once Weekly 70mg Tablets SmPC (revised 30 November 2023). medicines.org.uk/emc/product/1281/smpc |
Habits, and everything else
| The source | What the book says it shows, and where |
|---|---|
| Appel et al., NEJM 1997 (DASH, RCT, n=459).Established | Blood pressure fell 5.5 over 3.0 mmHg against control, and 11.4 over 5.5 in the 133 with hypertension. Eight weeks, all food provided, sodium and weight held constant: a blood-pressure trial rather than an outcome trial.Used on page 71 Full citationAppel et al. A clinical trial of the effects of dietary patterns on blood pressure. DASH Collaborative Research Group. N Engl J Med. 1997;336:1117-1124. doi:10.1056/NEJM199704173361601 · PMID 9099655 What the book does with itp71“DASH lowered blood pressure by 5.5 over 3.0 mmHg in eight weeks of controlled feeding, and more in people who already had hypertension (Appel 1997).” |
| Estruch et al., NEJM 2018 (PREDIMED, republished, n=7,447).Moderate | Fewer major cardiovascular events on a Mediterranean pattern, hazard ratios 0.69 and 0.72. The 2013 paper was retracted for randomization problems; in the 2018 reanalysis the authors changed “reduced” to “was lower among those assigned”. Graded for that.Used on page 71 Full citationEstruch et al. Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts. N Engl J Med. 2018;378:e34. doi:10.1056/NEJMoa1800389 · PMID 29897866 What the book does with itp71“PREDIMED found fewer cardiovascular events on a Mediterranean pattern, though it was retracted and republished in 2018 after randomization problems; the corrected report still finds fewer events in those assigned the diet, now stated with more caution (Estruch 2018).” |
| Schuster et al., Nat Sci Sleep 2025 (RCT, n=155).Emerging | Magnesium beat placebo on self-reported insomnia severity, p=0.049, effect size 0.2, no objective sleep measurement, and participants still subthreshold at the end. One author directs a research organization funded by supplement companies.Used on page 51 Full citationSchuster et al. Magnesium Bisglycinate Supplementation in Healthy Adults Reporting Poor Sleep: A Randomized, Placebo-Controlled Trial. Nat Sci Sleep. 2025;17:2027-2040. doi:10.2147/NSS.S524348 · PMID 40918053 What the book does with itp51“The largest trial found a small self-reported gain and recorded no objective sleep; the small crossover that did is the deep-sleep case on the page before, and the pooled older-adult trials are rated low quality (Schuster 2025; Mah 2021).” |
| Mah & Pitre, BMC Complement Med Ther 2021 (3 RCTs, n=151).Emerging | Sleep onset about 17 minutes faster than placebo in older adults, total sleep time unchanged. Graded down a step from its design because all three trials were at moderate to high risk of bias and the authors call the literature substandard for making recommendations, so magnesium is a convention in this book rather than a graded claim.Used on page 51 Full citationMah & Pitre. Oral magnesium supplementation for insomnia in older adults: a Systematic Review & Meta-Analysis. BMC Complement Med Ther. 2021;21:125. doi:10.1186/s12906-021-03297-z · PMID 33865376 What the book does with itp51“The largest trial found a small self-reported gain and recorded no objective sleep; the small crossover that did is the deep-sleep case on the page before, and the pooled older-adult trials are rated low quality (Schuster 2025; Mah 2021).” |
| Noetel et al., BMJ 2024 (network meta-analysis, 218 trials, n=14,170).Moderate | Exercise reduced depression against active controls, largest for walking or jogging, yoga and strength training. Graded down because the authors rated their own confidence low to very low, and only one trial met the Cochrane bar for low risk of bias.Used on page 71 Full citationNoetel et al. Effect of exercise for depression: systematic review and network meta-analysis of randomised controlled trials. BMJ. 2024;384:e075847. doi:10.1136/bmj-2023-075847 · PMID 38355154 What the book does with itp71“Exercise has real evidence for mood (Noetel 2024), and both sleep and exercise are in this book.” |
| Ekelund et al., BMJ 2019 (harmonized meta-analysis, 8 studies, n=36,383).Moderate | Accelerometer-measured sitting and all-cause mortality: hazard ratios of 1.00, 1.28, 1.71 and 2.63 across quarters, with risk climbing from about 7.5 to 9 hours a day. All studies from the US and western Europe, and the authors say reverse causation may persist.Used on page 44 Full citationEkelund et al. Dose-response associations between accelerometry measured physical activity and sedentary time and all cause mortality: systematic review and harmonised meta-analysis. BMJ. 2019;366:l4570. doi:10.1136/bmj.l4570 · PMID 31434697 What the book does with itp44“Total sitting matters too: measured by accelerometer, risk rises across the range, steepening past about 7.5 hours a day (Ekelund 2019).” |
| Araujo et al., BJSM 2022 (n=1,702, aged 51 to 75).Emerging | Failing a ten-second one-legged stance carried a higher risk of death over a median seven years, hazard ratio 1.84 adjusted. One exercise-medicine clinic, so the population is referred rather than general.Used on page 13 Full citationAraujo et al. Successful 10-second one-legged stance performance predicts survival in middle-aged and older individuals. Br J Sports Med. 2022;56:975-980. doi:10.1136/bjsports-2021-105360 · PMID 35728834 What the book does with itp13“Both track with survival in cohort studies (Araujo 2022, 2025).” And on page 13 the reader is told · In shortCheck off enough sleep at a regular time, eat better, and start moving. Ask your clinician how these apply if you take a regular medicine, are pregnant, or have a diagnosed condition |
| Araujo et al., Eur J Prev Cardiol 2025 (n=4,282, aged 46 to 75).Moderate | The sitting-rising test tracked with natural-cause and cardiovascular death over a median 12.3 years, hazard ratios 3.84 and 6.05 lowest scorers against highest. Same referred population, and the score moves with strength, flexibility and balance together.Used on page 13 Full citationAraujo et al. Sitting-rising test scores predict natural and cardiovascular causes of deaths in middle-aged and older men and women. Eur J Prev Cardiol. 2025. doi:10.1093/eurjpc/zwaf325 · PMID 40569873 What the book does with itp13“Both track with survival in cohort studies (Araujo 2022, 2025).” And on page 13 the reader is told · In shortCheck off enough sleep at a regular time, eat better, and start moving. Ask your clinician how these apply if you take a regular medicine, are pregnant, or have a diagnosed condition |
| Li et al., Circulation 2018 (n≈123,000).Moderate | Five habits tracked with ~12 to 14 more years at 50. Observational; sleep is not one.Used on page 12 Full citationLi et al. Impact of Healthy Lifestyle Factors on Life Expectancies in the US Population. Circulation. 2018;138:345-355. doi:10.1161/CIRCULATIONAHA.117.032047 · PMID 29712712 What the book does with itp12“At age 50, women with all five had roughly 14 more years of life expectancy than women with none, and men roughly 12 (Li 2018).” p12“Li 2018, observational: life expectancy at 50 with none vs all five of never smoking, healthy weight, daily activity, moderate alcohol, better diet” And on page 12 the reader is told · In shortRead the figure as the size of the association around basic habits, and how stacking them tracks with a meaningful difference |
| Wood & Rünger, Annu Rev Psychol 2016.Emerging | Habits are cue-driven and context-dependent. A narrative review, unpooled.Used on page 54 Full citationWood & Rünger. Psychology of Habit. Annu Rev Psychol. 2016;67:289-314. doi:10.1146/annurev-psych-122414-033417 · PMID 26361052 What the book does with itp54“What carries a behavior over months is a stable cue in a stable setting, with as little friction as possible (Wood & Rünger 2016).” p54“Wood and Rünger’s review makes the case that habits are cue-driven and context-dependent.” And on page 54 the reader is told · How to use itPut the gear where you cannot miss it, and keep the food you want at eye level and the food you do not want out of sight, or off your shopping list |
| Scullin et al., J Exp Psychol Gen 2018 (RCT, n=57, polysomnography).Emerging | Writing a to-do list before bed shortened time to fall asleep by about nine minutes against writing a list of what was already done.Used on page 58 Full citationScullin et al. The effects of bedtime writing on difficulty falling asleep: A polysomnographic study comparing to-do lists and completed activity lists. J Exp Psychol Gen. 2018;147:139-146. doi:10.1037/xge0000374 · PMID 29058942 What the book does with itp58“In the one trial I found (Scullin 2018, n=57, in a sleep lab), people who wrote a to-do list fell asleep about nine minutes faster than people who wrote down what they had done.” And on page 58 the reader is told · If you do one thing this week“When my wind-down starts, then I will spend five minutes writing tomorrow’s to-do list onto a pad, and put it away.” |
| Keller et al., Br J Health Psychol 2021 (RCT, n=192).Moderate | Habit stacking was no better than a plain time-of-day cue. A null in one trial. That is not demonstrated equivalence.Used on pages 54, 61 Full citationKeller et al. Habit formation following routine-based versus time-based cue planning: A randomized controlled trial. Br J Health Psychol. 2021;26:807-824. doi:10.1111/bjhp.12504 · PMID 33405284 What the book does with itp54“A later randomized trial in 192 people pitted anchoring a new habit to an existing routine against a plain time-of-day cue, and found no advantage for the anchored version (Keller 2021).” And on page 54 the reader is told · How to use itPut the gear where you cannot miss it, and keep the food you want at eye level and the food you do not want out of sight, or off your shopping list |
| Dai, Milkman & Riis, Manage Sci 2014.Emerging | Fresh-start dates lift starts after a landmark. Archival work plus one short-lived field experiment.Used on page 55 Full citationDai, Milkman & Riis. The Fresh Start Effect: Temporal Landmarks Motivate Aspirational Behavior. Manage Sci. 2014;60:2563-2582. doi:10.1287/mnsc.2014.1901 What the book does with itp55“Fresh starts spike after a landmark date, a Monday or the first of the month (Dai 2014), and pairing something you want with something you should do raised gym attendance in a controlled study (Milkman 2014).” |
| Milkman, Minson & Volpp, Manage Sci 2014 (single field experiment).Emerging | Temptation bundling, gym-only access to audiobooks, raised gym visits by about half at first, fading across the study, as the authors report. One field experiment standing on its own.Used on page 55 Full citationMilkman, Minson & Volpp. Holding the Hunger Games Hostage at the Gym: An Evaluation of Temptation Bundling. Manage Sci. 2014;60:283-299. doi:10.1287/mnsc.2013.1784 · PMID 25843979 What the book does with itp55“Fresh starts spike after a landmark date, a Monday or the first of the month (Dai 2014), and pairing something you want with something you should do raised gym attendance in a controlled study (Milkman 2014).” |
| Harkin et al., Psychol Bull 2016 (138 studies).Established | Progress monitoring improved goal attainment; writing it down worked best. Publication-bias risk here, so read d=0.40 as the top of a range; capped at Established for that.Used on page 54 Full citationHarkin et al. Does monitoring goal progress promote goal attainment? A meta-analysis of the experimental evidence. Psychol Bull. 2016;142:198-229. doi:10.1037/bul0000025 · PMID 26479070 What the book does with itp54“This literature carries the usual publication-bias risk, so read that as the top of a range (Harkin 2016).” p54“Harkin and colleagues pooled 138 experiments.” And on page 54 the reader is told · How to use itOne line a day on paper is enough, or a mark on a wall calendar. It works best somewhere you walk past anyway |
| Gollwitzer & Sheeran, Adv Exp Soc Psychol 2006 (meta, 94 tests).Moderate | If-then plans close the intention-action gap, pooled d≈0.65. Largest for one-off actions, smaller for sustained change, and predating routine bias correction. Capped at Established for that, then down a step because the 2024 pooling corrects it.Used on pages 54, 61 Full citationGollwitzer & Sheeran. Implementation Intentions and Goal Achievement: A Meta-analysis of Effects and Processes. Adv Exp Soc Psychol. 2006;38:69-119. doi:10.1016/S0065-2601(06)38002-1 What the book does with itp54“It reports an effect size and no follow-through rate, so do not convert it into a percentage (Gollwitzer & Sheeran 2006).” p54“An implementation intention reads “when [something I already do], then I will [the small version].” Gollwitzer & Sheeran pooled 94 independent tests.” And on page 54 the reader is told · How to use itTake the change you keep postponing and name the exact moment it happens. “I will exercise more” is a goal. “When I finish lunch on Monday, I walk for fifteen minutes” is a plan |
| Sheeran, Listrom & Gollwitzer, Eur Rev Soc Psychol 2024 (online; 2025 volume; meta, 642 tests).Established | The same group, pooling 642 tests against the 94 of 2006. Publication bias was substantial; the two standard corrections put the effect at d≈0.35 and d≈0.15. Real, and smaller than the headline.Used on page 54 Full citationSheeran, Listrom & Gollwitzer. The when and how of planning: Meta-analysis of the scope and components of implementation intentions in 642 tests. Eur Rev Soc Psychol. 2024;36:162-194. doi:10.1080/10463283.2024.2334563 What the book does with itp54“Sheeran, Listrom and Gollwitzer pooled 642 tests in 2024 and found substantial publication bias.” p54“Correcting for it drops the effect to between d≈0.15 and d≈0.35, depending on the correction (Sheeran 2024).” And on page 54 the reader is told · How to use itTake the change you keep postponing and name the exact moment it happens. “I will exercise more” is a goal. “When I finish lunch on Monday, I walk for fifteen minutes” is a plan |
| Lally et al., Eur J Soc Psychol 2010.Emerging | Median ~66 days across 39 usable curves from 96 volunteers, over 12 weeks. One observational study on its own.Used on pages 53, 61 Full citationLally et al. How are habits formed: Modelling habit formation in the real world. Eur J Soc Psychol. 2010;40:998-1009. doi:10.1002/ejsp.674 What the book does with itp53“The median was about 66 days across those curves, in a study that ran twelve weeks (Lally 2010).” p53“Lally and colleagues timed 96 volunteers adopting one, of whom 39 produced usable curves.” And on page 53 the reader is told · How to use itExpect months more often than weeks. Treat week four still feeling like effort as the normal course |
| Hagger et al., Perspect Psychol Sci 2016 (Registered Replication).Strong | The “willpower muscle” failed to replicate across 23 labs.Used on pages 10, 53, 61 Full citationHagger et al. A Multilab Preregistered Replication of the Ego-Depletion Effect. Perspect Psychol Sci. 2016;11:546-573. doi:10.1177/1745691616652873 · PMID 27474142 What the book does with itp10“If you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower.” And on page 10 the reader is told · Ten sources firstIf you read only ten sources, read these: Windred 2024 on regularity, Gardiner 2023 on caffeine, Qaseem 2016 on CBT-I, Reynolds 2019 on fiber, Morton 2018 on protein, the AHA Presidential Advisory on fat, Momma 2022 on strength, Ding 2025 on steps, Sherrington 2019 on balance, and Hagger 2016 on willpower. Every one is in the source list with its grade. Their DOIs, in that order, so the paper copy stands on its own: 10.1093/sleep/zsad253; 10.1016/j.smrv.2023.101764; 10.7326/M15-2175; 10.1016/S0140-6736(18)31809-9; 10.1136/bjsports-2017-097608; 10.1161/CIR.0000000000000510; 10.1136/bjsports-2021-105061; 10.1016/S2468-2667(25)00164-1; 10.1002/14651858.CD012424.pub2; 10.1177/1745691616652873. Each checked on PubMed p53“The effect came out indistinguishable from zero, with a confidence interval straddling it (Hagger 2016).” And on page 53 the reader is told · How to use itStop treating adherence as a character test. If something keeps failing, look for a better cue or less friction |
| Bouchard et al., J Appl Physiol 1999 (HERITAGE, n=481).Moderate | How much people gained clustered within families on one supervised protocol, which is what this study measured. Whether individuals truly differ in trainability is a separate question it did not test.Used on page 56 Full citationBouchard et al. Familial aggregation of VO(2max) response to exercise training: results from the HERITAGE Family Study. J Appl Physiol (1985). 1999;87:1003-1008. doi:10.1152/jappl.1999.87.3.1003 · PMID 10484570 What the book does with itp56“How much people gained clustered strongly within families (Bouchard 1999).” And on page 56 the reader is told · How to use itIf three months (a convention) of one kind of training moves nothing, change the stimulus, intensity or modality before deciding your body is the problem |
The studies behind what I left out
| The source | What the book says it shows, and where |
|---|---|
| Lincoff et al. (SELECT), NEJM 2023 (RCT, n=17,604).Established | Semaglutide cut cardiovascular events in people with overweight or obesity and heart disease; diabetes excluded. Outside this book’s scope, inside its evidence bar.Used on page 71 Full citationLincoff et al. (SELECT). Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes. N Engl J Med. 2023;389:2221-2232. doi:10.1056/NEJMoa2307563 · PMID 37952131 What the book does with itp71“The evidence is not thin: semaglutide cut cardiovascular events in 17,604 people with overweight or obesity and established heart disease, diabetes excluded (SELECT, Lincoff 2023), and tirzepatide is licensed in the United States for moderate-to-severe sleep apnea in adults with obesity, on the back of SURMOUNT-OSA, though not everywhere and not for sleep apnea on its own.” |
| SURMOUNT-OSA, NEJM 2024 (RCTs).Established | Tirzepatide reduced obstructive sleep apnea severity; licensed on that basis in the US, though not everywhere.Used on page 71 Full citationMalhotra et al. (SURMOUNT-OSA). Tirzepatide for the Treatment of Obstructive Sleep Apnea and Obesity. N Engl J Med. 2024;391:1193-1205. doi:10.1056/NEJMoa2404881 · PMID 38912654 What the book does with itp71“The evidence is not thin: semaglutide cut cardiovascular events in 17,604 people with overweight or obesity and established heart disease, diabetes excluded (SELECT, Lincoff 2023), and tirzepatide is licensed in the United States for moderate-to-severe sleep apnea in adults with obesity, on the back of SURMOUNT-OSA, though not everywhere and not for sleep apnea on its own.” |
| Holt-Lunstad et al., PLoS Med 2010 (meta).Moderate | Strong social ties predict ~50% higher survival odds; associational.Used on page 71 Full citationHolt-Lunstad et al. Social relationships and mortality risk: a meta-analytic review. PLoS Med. 2010;7:e1000316. doi:10.1371/journal.pmed.1000316 · PMID 20668659 What the book does with itp71“Not dismissed, and strong ties predict about 50% higher survival odds (Holt-Lunstad 2010).” |