A new study suggests that the global surge in obesity is being fueled more by increased calorie consumption than by a drop in physical activity.
Contrary to the long-held belief that industrialization and sedentary lifestyles are to blame, researchers from Duke University in the United States found that individuals in wealthier nations often burn the same-or even greater-amounts of energy as those in less affluent regions.
“The evidence strongly points to diet changes, rather than decreased physical activity, as the leading factor behind rising obesity,” said Professor Herman Pontzer, the study’s lead author and a faculty member in Duke’s Department of Evolutionary Anthropology.
Published in the journal PNAS, the research analyzed over 4,200 adults between the ages of 18 and 60 across 34 diverse populations on six continents. The team examined data on total daily energy expenditure, body fat percentage, and body mass index (BMI).
While the study noted a slight decline in total energy expenditure adjusted for body size in more economically developed regions, these changes accounted for only a small portion of the rise in body fat. The findings point to increased calorie intake as the primary contributor to the obesity crisis.