From "Canadian Running Magazine": "It seems that a lack of physical activity is more at fault for the rising levels of obesity in North America than increases in caloric intake. A new study, dating back 20 years to 1994, has found that while waistlines increased over the past two decades, caloric intake stayed largely even. What did negatively correlate with increases in obesity rates was the amount of exercise and activity of the general population. In 1994, 19.1 per cent of American women reported getting no physical activity. In 2010, that number had jumped to over half at 51.7 per cent. In men, the rate jumped from 11.4 per cent to 43.5 per cent. The most dramatic increase came in young women between the ages of 18 and 39. The study, published in the American Journal of Medicine, didn’t find any relationship between rising levels of obesity and caloric intake, even though that is a subject commonly cited as a main cause for what has been deemed by some as an “epidemic.”
“Our findings do not support the popular notion that the increase of obesity in the United States can be attributed primarily to sustained increase over time in the average daily caloric intake of Americans,” said lead investigator Uri Ladabaum in a release. The study was done with American subjects, but similar trends have been observed in Canada in regards to sedentary lifestyles and obesity."