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Topic: Food

Food and evolution: what the evidence says

Everything this site carries on food, gathered in one place: the book's chapters and where they say to start, every popular claim they grade, and the reference topics and terms behind them.

1 chapter of the book5 graded claims10 reference topics323 sources

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Where does the book say to start on food?

Chapter 5: Eat

  1. Cut the ultra-processed share first, beginning with sugary drinks and processed meat

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

  2. Build meals on plants, legumes, and minimally processed protein and fats

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

  3. Drink to thirst

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

The full protocol for Chapter 5

Which popular claims about food hold up?

What does the body expect, and what does it get now?

The mismatch cards of the reference topics behind these chapters, as the library states them.

  • Topic 3: The Expensive Organ

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

    The brain and the mental habits it runs.

    What it expects
    Cooked, varied food; sleep; a band of about 30 people inside a wider network; daily physical and mental challenge.
    What it gets
    Long hours seated (Topic 6), isolation for some, and prices, deadlines and risks its defaults never met.
    What happens in the gap
    Defaults misfire as worry, the planning fallacy and reluctance to part with what you own; isolation and inactivity are associated with smaller brain structures and higher dementia risk.

  • Topic 11: The Hijacked Reward System

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

    The reward system (dopamine-driven wanting, opioid and endocannabinoid liking) and the appetite it steers.

    What it expects
    Sugar that costs effort or comes wrapped in fruit, ethanol at a fraction of a percent, and food that takes time to chew.
    What it gets
    Ultra-processed food supplying 55% of American calories, and alcohol in concentrated drinks.
    What happens in the gap
    Faster eating and about 500 kcal a day of extra intake in a controlled trial; 2.6 million alcohol-attributable deaths a year.

  • Topic 13: The Thrifty Body

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

    Energy storage and appetite: fat, the hormones that report on it, and the muscle, liver and pancreas that handle fuel.

    What it expects
    Food that takes work to get, lean seasons, fiber-rich plants and hours of physical work.
    What it gets
    Cheap, energy-dense, ultra-processed food all day, little physical work and short sleep.
    What happens in the gap
    Fat accumulates, a body built to defend its stores resists losing it, and fat that overflows into liver, muscle and pancreas is thought to drive insulin resistance and type 2 diabetes.

  • Topic 14: The Liver and the Chemical Century

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

    The liver, first stop for most of what the gut absorbs: chemical defense and fuel storage.

    What it expects
    Daily plant defense chemicals, occasional natural toxins such as aflatoxin, and food energy that took work to get.
    What it gets
    Surplus calories from sugary drinks and alcohol, and more than 350,000 registered chemicals and mixtures, a few of them, such as the long-lived PFAS, beyond its power to break down.
    What happens in the gap
    About 30% of adults worldwide have fatty livers, and more of them die of heart disease than of liver disease; the main PFAS linger for years in nearly every American's blood.

  • Topic 15: The Tongue and the Nose

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

    Taste and smell, the chemical senses that judge food and air.

    What it expects
    Sugar wrapped in fiber, bitter and sour plants, and a nose used daily to find food and judge freshness.
    What it gets
    Sugar dissolved in drinks at all hours, debittered crops, sweeteners, polluted air, smoke, viruses and an underused nose.
    What happens in the gap
    Easy sugar overconsumption, lost bitter warnings, and unnoticed smell loss linked to higher mortality.

  • Topic 17: The Water You Forgot to Drink

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

    Water balance: thirst, kidneys and vasopressin.

    What it expects
    Wet food and drinking to thirst, in an ape that turns over 30% to 50% less water than its cousins, size for size.
    What it gets
    Taps, climate control, a 1945 allowance stripped of its caveats, and a market selling hydration.
    What happens in the gap
    Little, for most healthy people. In long events, overdrinking can dilute blood sodium and swell the brain; thirst lags in older people and in heat.

  • Topic 4: The Last Ice Age and the Birth of Agriculture

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

    The agricultural body: a forager's physiology, partly retuned since farming began.

    What it expects
    A varied diet of wild plants and animals, daily walking and carrying, small mobile groups, seasonal variety.
    What it gets
    Cereals supplying 42% of the world's dietary energy, sedentary work, and dense settlements shared with animals and strangers.
    What happens in the gap
    In early farmers, on average: shorter stature, more tooth decay and infection, heavy repetitive labor. Since then, immune genes have been retuned against new pathogens, possibly at the cost of more inflammatory and autoimmune risk.

  • Topic 16: The Shrinking Face

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

    The face, jaws, teeth and upper airway.

    What it expects
    Hard chewing from childhood, teeth that wear flat, a clear nose, little free sugar.
    What it gets
    Soft processed food, fork-cut mouthfuls, industrial flour and sugar, and more body weight pressing on the airway.
    What happens in the gap
    Jaws that fall short of their teeth (crowding, impacted wisdom teeth), retained overbites, widespread decay, and possibly, alongside weight, some sleep apnea.

  • Topic 37: The Individual Variable

    StrongEvidence grade: Strong. Multiple randomized controlled trials, or consistent large cohort studies with a well-understood mechanism.

    Local genetic adaptation: the regional tuning of digestion, metabolism, blood and breath laid down over the last few thousand years.

    What it expects
    The diet, altitude, sunlight and pathogens of the place where your recent ancestors lived and reproduced.
    What it gets
    Global food supply, air travel, latitude changes within a single lifetime, and a consumer test that reports ancestry as if it reported physiology.
    What happens in the gap
    Mostly small mismatches (the dairy that disagrees, the flush after one glass), occasionally serious ones (sickle trait far from malaria, vitamin D deficiency far from the equator), and a steady traffic in genetic advice that outruns the evidence.

  • Topic 40: The Handrail I: Move, Eat, Drink

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

    Skeletal muscle, heart and lungs, the gut and the thirst reflex, all of them signal-driven.

    What it expects
    Several hours a day of unremarkable movement, occasional hard bursts, loads carried, food that spoils, and water when thirsty.
    What it gets
    About 5,100 steps, chairs, engines, food engineered to be eaten quickly, and a hydration industry.
    What happens in the gap
    Systems tuned by use drift downward in their sleep, and the drift shows up decades later as disease.

Terms

The chapters and reference topics on this page cite 323 distinct works, each listed on its own page and in the source register. Educational content, not medical advice; read the disclaimer.