As our country's obesity problem has gained more attention in recent years, many have looked to identify the root of the problem. A recent 20-year study conducted by Stanford University revealed that obesity is not due primarily to over-eating but rather a decline in exercise, which leads to increases in average body mass index (BMI). Categories examined by lead author Uri Ladabaum and his colleagues include: obesity, waistline obesity, physical activity and calorie intake. 

"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 Ladabaum, an associate professor of medicine at Stanford. "We found a significant association between the level of leisure-time physical activity, but not daily caloric intake, and the increases in BMI and waist circumference."

In 1994, only 19.1 percent of women admitted to not having any physical activity in their lifestyle, but by 2010, 51.7 percent for women reported that they did not work out. Men only produced 11.4 percent of those who didn't work out in 1994, but saw an increase in 2010 to 43.5 percent. BMI has increased 0.37 percent per year for women and 0.27 percent for men. The researchers found this was the case for both normal-weight and overweight women, while only for overweight men.

Racial groups hit hardest by lack of exercise are African-American and Mexican-American women, according to the study. 

avatar
I disagree with the conclusions drawn here. I feel that the QUALITY of food eaten is very poor and also poorly timed, even if total caloric intake is not changed. Folks eat the wrong things at the wrong times. 3000 calories of Doritos gone in one sitting won't be the same as 3000 calories spaced out over 5 meals consisting of lean healthy proteins, vegetables and fats will not lead to the same physique. Lack of nutritional knowledge is absolutely a problem, and while I am not discounting physical activity as a beneficial means to minimize obesity, you cannot out-exercise a bad diet.
avatar
So why have the major junk food companies increased dramatically over the past few decades? As Craig mentioned people are eating more processed foods that have less nutritional value not to mention the 32oz soft drinks weren't around 20 years ago.
avatar
I agree with both Craig and David about the importance of nutrition, however, I disagree with the comment on calories. A person (void of any serious medical condition) could have an ideal BMI from consuming pizza and soda. Conversely, a person could also have an undesirable BMI from eating the exact same food. The article is validation that a calorie is still a calorie. It's all about burning more energy than you take in.
avatar
As a 220 lb. bodybuilder and a physician, I will discredit BMI as anything valuable for determining true health and I will promise that a calorie is not "just a calorie" in determining body composition. Needless to say, BMI has nothing to do with body composition, so if that's all you're saying, fine. However, I will say that I'll take my 220 12% BF compared to a 220 40% BF and challenge that my overall health is far greater.
avatar
@Craig, nothing against you personally but may doctors give nutritional advice to patients but have no formal training on nutrition. I have 2 young active boys and I have the opposite problem that I can't get enough calories into them but I try to keep them away from junk food which is tough in today's world since it is everywhere.