Spiral Staircase: evolutionary mismatch, graded by the evidence

1. 1

   Don't smoke, and drink little or nothing

   no cigarettes, with medication or a regulated e-cigarette to get there. Alcohol, if any, kept low; two or fewer standard drinks a week is the low-risk band.

   ●●●StrongEvidence grade: Strong. Multiple randomized controlled trials, or consistent large cohort studies with a well-understood mechanism.●●○ProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.
2. 2

   Move: walk, lift, and hurry now and then

   walk toward seven or eight thousand steps a day, from wherever you are; two strength sessions a week of about half an hour; a few short bursts of hard effort a day.

   ●●●StrongEvidence grade: Strong. Multiple randomized controlled trials, or consistent large cohort studies with a well-understood mechanism.●●○ProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.
3. 3

   Eat: subtract first

   swap the meals you eat most often for versions built from ingredients, then add plants and legumes.

   ●●○ProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.
4. 4

   Sleep: keep regular times

   the same wake time every day, weekends included; outdoor daylight early; a dark bedroom.

   ●●○ProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.●○○EmergingEvidence grade: Emerging. Early, small, animal-only, or actively contested.
5. 5

   People: an inner circle you actually see

   name three to five people and put recurring, in-person contact with them in the calendar; add one standing weekly thing done with others.

   ●●○ProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.●○○EmergingEvidence grade: Emerging. Early, small, animal-only, or actively contested.

6. The book ranks them first, gives each a dose and a grade, and then spends fifteen chapters on the body and mind behind them.

   All sixteen chapters

The book in six parts

Start with Chapter 1. After the first two, every chapter stands on its own: open the one that describes the problem you have.

• Part 1

  The Short Version

  1. The Short Version. 2. What Your Body Expects, and How to Trust This Book.

  2 chapters
• Part 2

  The Body That Moves

  3. The Body That Walks. 4. Load, Strength and Bone.

  2 chapters
• Part 3

  The Body That Eats

  5. Eat. 6. The Gut That Expects Dirt.

  2 chapters
• Part 4

  The Body That Reads Signals

  7. Light and Dark. 8. Sleep. 9. Heat and Cold. 10. Green and Quiet.

  4 chapters
• Part 5

  The Social Animal

  11. The Social Animal. 12. Attention in the Age of the Phone. 13. Stress and the Mind. 14. Wanting, Loving, Losing, Meaning.

  4 chapters
• Part 6

  The Life Course

  15. Women's Bodies Across the Life Course. 16. Aging Well.

  2 chapters

All sixteen chapters

1. Chapter 1: The Short VersionThe short version: the five things that matter most
2. Chapter 2: What Your Body Expects, and How to Trust This BookHow to trust health advice: what your body evolved to expect
3. Chapter 3: The Body That WalksWalking, sitting and steps: what the evidence says
4. Chapter 4: Load, Strength and BoneStrength training and bone health: what the evidence says
5. Chapter 5: EatWhat to eat, and ultra-processed food: the evidence
6. Chapter 6: The Gut That Expects DirtGut health, fiber and allergies: what the evidence says
7. Chapter 7: Light and DarkLight, the body clock and vitamin D: where to start
8. Chapter 8: SleepSleep: what the evidence says, and where to start
9. Chapter 9: Heat and ColdCold exposure, sauna and heat: what the evidence says
10. Chapter 10: Green and QuietNature, green space and noise: what the evidence says
11. Chapter 11: The Social AnimalLoneliness and health: why connection matters
12. Chapter 12: Attention in the Age of the PhonePhones and attention: what screens do, and where to start
13. Chapter 13: Stress and the MindStress, anxiety and cortisol: what the evidence says
14. Chapter 14: Wanting, Loving, Losing, MeaningAddiction, love, grief and meaning: what the evidence says
15. Chapter 15: Women's Bodies Across the Life CourseWomen's health from periods to menopause: the evidence
16. Chapter 16: Aging WellAging well: what the evidence says, and where to start

Want the longer treatment of a topic? The reference library has 45 in-depth entries, each linked to the chapter of the book that covers it.