A groundbreaking study published in the Proceedings of the National Academy of Sciences (PNAS) challenges the long-held belief that physical inactivity is the primary driver of obesity. The research, involving over 4,000 adults from 34 diverse populations worldwide, reveals that excessive calorie intake, particularly from ultra-processed foods, is roughly 10 times more significant than reduced physical activity in fueling the global obesity crisis. Key Findings of the Study Led by Herman Pontzer, a professor of evolutionary anthropology at Duke University, the study analyzed energy expenditure using doubly labeled water, a gold-standard method for measuring daily calorie burn. Researchers examined total energy expenditure (TEE), basal metabolic rate (BMR), and activity energy expenditure (AEE) across groups ranging from hunter-gatherers in Tanzania to...