Overview
- The peer-reviewed analysis, published Thursday, August 6, 2026, in Science, uses a new model to estimate how ancestral diets supplied glucose as hominin brains enlarged.
- Authors calculated an organism’s “obligatory glucose demand” — the glucose the brain and other tissues must have — and compared that need to likely carbohydrate sources across six evolutionary stages.
- The team estimates earliest chimpanzee-like hominins derived more than two-thirds of dietary energy from fruit and similar sweet foods and that natural sugars supplied about 20 to 35 percent of energy on average over four million years.
- The paper stresses sugars as a complementary fuel rather than a replacement for animal foods, and it points to supporting clues such as fossil tooth decay, isotope signals, color vision for ripe-fruit detection, and genetic changes in sugar metabolism.
- Researchers and outside experts praise the synthesis but note key uncertainties in the work’s assumptions and proxy data, and they say further fossil, isotopic and archaeological evidence is needed to refine the proportions and test the model’s implications for modern nutrition and human life history.