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Glossary

Drunken monkey hypothesis

Defined in topic 11

Robert Dudley's proposal that the smell of ethanol in ripening fruit led ancestral primates to food, and that modern drinking misfires that attraction. Wild chimpanzee fruit averages 0.3% ethanol.

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Where this comes from

In the reference topic that owns this term

Reference topic 11, The Hijacked Reward System, states the mismatch as a card: what the system evolved to expect, what it gets instead, and what happens in the gap.

Mismatch card

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.

The full card, and the topic behind it

What that chapter recommends

3 of the 5 graded recommendations in Reference topic 11, strongest evidence first. How the grades work.

  1. Add friction

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

    Keep hyper-palatable snacks out of sight and reach, and make whole foods the easy option at home and at work. Moving food farther away reduced how much people ate (low-certainty evidence).

    Read it in full

  2. Swap whole meals

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

    Start with the meals you eat most often. On a metabolic ward, people ate about 500 kcal a day less on minimally processed menus than on ultra-processed ones.

    Read it in full

  3. Shrink portions and slow down

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

    Smaller portions, packages and plates reduce intake, modeled at 144-228 kcal a day if sustained across the whole diet. Eating more slowly lowers intake without leaving people hungrier over the next few hours. ●●○

    Read it in full

Related terms

The argument behind this term, its studies and its notes are in Reference topic 11 of the reference library. The book gives the practical version. Get the book.