Obesity Rates Jumped Worldwide Around 1980 — And No One Knows Why

A Chemical Hunger (2021)

A century ago, the average American man weighed about 155 pounds and only 1% of the population was obese; today those figures are roughly 195 pounds and 36%. The rise wasn't gradual: obesity held steady near 10% in developed countries until 1980, then climbed sharply. Oddly, lab animals, pets, and even wild creatures are also getting fatter on unchanged diets, while hunter-gatherer groups eating sugar- and fat-heavy diets stay lean. Something changed — and the usual explanations don't fit.