A trio of researchers with varied backgrounds is suggesting in an article published in the journal Communications Biology that eating naturally fermented foods may have led to an increase in brain size for early humans. In their paper, Katherine Bryant, a psychologist at Aix-Marseille Université, Christi Hansen, a dietician at Hungry Heart Farm and Dietary Consulting, and Erin Hecht, a biologist at Harvard University, suggest that eating naturally fermenting foods may also have led to a decrease in the size of the colon.