Apples for Health- Calorie increase explains U.S. weight gain

Calorie increase explains U.S. weight gain

DEAKIN, Australia, May 12 (UPI) -- The rise in obesity in the United States since the 1970s was virtually all due to increased calorie intake, researcher in Australia concluded.

Boyd Swinburn of Deakin University in Australia and colleagues tested 1,399 adults and 963 children to determine how many calories their bodies burn.

The researchers calculated how much adults needed to eat to maintain a stable weight and how much children needed to eat to maintain a normal growth curve.

The researchers calculated how much Americans were eating, using data on the amount of food produced and imported, minus the amount exported, thrown away and used for animals or other non-human uses from the 1970s to 2000s. The researchers used data from a nationally representative survey that recorded the weight of Americans in the 1970s and early 2000s.

The researchers found that in children, the predicted and actual weight increase matched exactly -- indicating that the increases in calorie intake alone could explain the weight increase over the 30-year period.

"For adults, we predicted that they would be about 24 pounds heavier, but in fact they were about 19 pounds heavier," Swinburn said in a statement. "That suggests that excess food intake still explains the weight gain, but that there may have been increases in physical activity over the 30 years that have blunted what would otherwise have been a higher weight gain."

The findings were presented at the European Congress on Obesity in Amsterdam.