Adrian Woolfson reviews Harvard paleoanthropologist Daniel E. Lieberman’s Fed Up: What Evolution Reveals About Food, Diet, Health, and Eating Well — an evolutionary case against dietary absolutism. Lieberman’s thesis: the question of what we should eat is “far too complex to be solved by a single Big Idea,” and every grand dietary theory crashes into the same fact — for most of human existence we lived in the shadow of starvation, so our bodies evolved to stockpile energy rather than shed it.
The uncomfortable biology first:
- Two-thirds of Americans are overweight, with body fat exceeding that of Arctic seals
- Obesity doesn’t add fat cells — each cell expands like an “overstuffed suitcase,” driving chronic inflammation and raising risks of Alzheimer’s and cancer
- Obesity is a modern phenomenon, vanishingly rare among hunter-gatherers; Stone Age Venus figurines’ rotundness was likely aspirational
The fad-diet takedowns:
- Paleo (Loren Cordain, 2002): the idea of a unitary Paleolithic diet is a “naturalist fallacy” — hunter-gatherer diets varied widely
- Raw food: “If raw food is best, why is cooking practiced and enjoyed by just about everyone on the planet?”
- Mediterranean: never a single diet — tomatoes arrived in Italy in the 16th century but entered the national canon only two centuries later
The positive case: Blue Zones like Loma Linda, California, where Seventh-day Adventists are mostly vegetarian, abstain from alcohol and tobacco, and keep close-knit social networks — no single principle explains their longevity.
The real enemy, Lieberman argues, is ultraprocessed food — the “obesity pandemic” as evolutionary mismatch, engineered to trigger “primeval cravings” and hijack the brain’s reward centers.
His prescription is almost Epicurean: eat less, drink more water, exercise, avoid excess sugar, and enjoy the “glorious diversity of foods” — “be moderate to taste the joys of life in abundance.” A welcome counter to the next diet that promises one big answer.