Conventional wisdom regarding the association of diet and exercise with weight loss and maintenance dictates that a combination is required to achieve desired results. Not so, says a new Duke University study…
What they did
“The researchers analyzed thousands of measurements of daily energy expenditure, body fat percentage and body mass index (BMI) from adults aged 18 to 60 across 34 populations spanning six continents,” an abstract of the Study Report reports.
“The more than 4,200 adults included in the study came from a wide range of lifestyles and economies, including hunter-gatherer, pastoralist, farming and industrialized populations. To further categorize the level of industrialization, they also integrated data from the United Nations Human Development Index (HDI) to incorporate measures of lifespan, prosperity and education.”
“This large, international, collaborative effort allow[ed] us to test these competing ideas,” says Herman Pontzer, principal investigator with the Pontzer Lab and professor in Duke’s Department of Evolutionary Anthropology.
What they found
“It’s clear that changes in diet, not reduced activity, are the main cause of obesity in the U.S. and other developed countries,” Pontzer confirms.
It says something that the study – no matter how counterintuitive in its findings – was judged suitable and meritorious enough for publication in the high-respected Proceedings of the National Academy of Sciences (PNAS).
The takeaway
The researchers hope the study helps clarify public health messaging [about obesity], and strategies to tackle the obesity crisis.
Specifically, they hope to show conclusively that the findings […] support an emerging consensus that both diet and exercise have their place in the war against weight. “Diet and physical activity should be viewed as essential and complementary, rather than interchangeable,” the study notes.
The team will next work to identify which aspects of diet in developed countries are most responsible for the rise in obesity.
My take
My first impression was, “Drat! – Decades of intuition-supported conventional wisdom down the drain!”
On the other hand, I was always suspicious of studies and ‘learned opinions’ that activity levels were more important than diet in determining whether we, as individuals, were likely to win or lose the Obesity War.
Clearly, the surprising counterintuitive central finding of the study points to the need for further research on how exercise, diet and all the other contributing factors come together to determine whether some of us will become obese and others not…
And the sooner the better!
~ Maggie J.