EATING? –
July 15, 2025 – A new study finds that Americans, Europeans and people living in other developed nations expend about the same number of total calories most days as hunter-gatherers, herders, subsistence farmers, foragers and anyone else living in less-industrialized nations. That unexpected finding almost certainly means inactivity is not the main cause of obesity in the U.S. and elsewhere…
“There’s still a lively debate in public health about the role of diet and activity” in the development of obesity, Pontzer said, especially in wealthy nations. Some experts believe we’re exercising too little, others that we’re eating too much, and still more that the two contribute almost equally.
Understanding the relative contributions of diet and physical activity is important, Pontzer noted, because we can’t effectively help people with obesity unless we first tease out its origins. But few large-scale studies have carefully compared energy expenditure among populations prone to obesity against those more resistant to it, which would be a first step toward figuring out what drives weight gain.
