According to the evolutionary anthropologist Herman Pontzer the amount of calories a human burns each day is very similar, with low activity Europeans and Americans burning just as many calories per day as African hunter-gatherers who walk 14 km a day.
How is that possible? Science.org°:
Pontzer thinks hunter-gatherers’ bodies adjust for more activity by spending fewer calories on other unseen tasks, such as inflammation and stress responses. “Instead of increasing the calories burned per day, the Hadza’s physical activity was changing the way they spend their calories,” he says.
Also, humans burn a hell of a lot of calories compared to apes:
Subsequent doubly labeled water studies of apes in captivity and in sanctuaries shattered the consensus view that mammals all have similar metabolic rates when adjusted for body mass. Among great apes, humans are the outlier. When adjusted for body mass, we burn 20% more energy per day than chimps and bonobos, 40% more than gorillas, and 60% more than orangutans, Pontzer and colleagues reported in Nature in 2016.
Why? Mostly, it’s our big brains:
But humans have an added energy expense: our big brains, which account for 20% of our energy use per day.
He also confirms something that’s very important to know if you’re currently trying to lose weight. And that’s that exercise doesn’t really help you lose weight:
Pontzer’s findings have a discouraging implication for people wanting to lose weight. “You can’t exercise your way out of obesity,” says evolutionary physiologist John Speakman of the Chinese Academy of Sciences. “It’s one of those zombie ideas that refuses to die.” Already the research is influencing dietary guidelines for nutrition and weight loss. The U.K. National Food Strategy, for example, notes that “you can’t outrun a bad diet.”
Fascinating stuff. Read the whole article°.
