UVA Scientists Say Exercise Is Better Than Weight Loss to Prevent Diseases and Death
Siddhartha Angadi is a Professor in the Department of Kinesiology at UVA – a man devoted to understanding the relationship between weight, exercise and health.
“I’m a cardiovascular exercise physiologist," he explains. "I look at the effects and interactions of everything from exercise to diet and drugs, health and disease – primarily looking at cardiovascular conditions where obesity is a risk factor.”
And this month he and a colleague at Arizona State University shared findings from a massive review of studies on weight and fitness.
“We have about 225 references in this article. It was a beast,” Angadi says.
His findings were so surprising that they’ve attracted attention from around the world.
“We got contacted by Swedish public radio yesterday!" he recalls. "It happened the instant it came out of embargo at 11 a.m.”
What he and Professor Glenn Gaesser concluded was that overweight and obese people can be fit – and that reduces the risk of cardiovascular disease, diabetes and cancer more than losing weight.
“When you exercise and improve your cardiovascular fitness or if you just improve your physical activity, you observe considerable improvements in your health status, disease status and reductions in your risk of mortality,” Angadi says.
The studies assessed patient health based on blood pressure, insulin sensitivity, cholesterol levels, artery function and something called VO2 Max.
“We measured the oxygen going in, the oxygen coming out, and we can get a measure of what your whole body’s oxygen consumption is, and it’s an incredibly powerful tool for predicting the risk of mortality and disease in a lot of populations.”
The conclusion – that exercise can reduce the risk of disease and death associated with obesity—is good news, Angadi says, because few people can lose weight and keep it off.
“If you look at the long-term success rate of weight loss attempts, they are extraordinarily poor.”
Angadi points out that a tendency to weight gain may be inherited, and the body may resist weight loss.
“If you ask the average person on the street why people fail and losing weight and keeping it off they would probably say it’s because people cheat or they can’t stick to their diet or their exercise program, whereas what we really know is when you’re obese, you have differences in your physiological regulation of body weight. When you start losing weight, your body adapts its metabolism to deal with this reduction in calories, and that’s a large reason why people regain the weight that they lost in the first place. Even the hormones that tell you when to eat and stop eating, they don’t work as advertised after you stop losing weight.”
And frankly, he adds, repeated weight loss and gain can lead to muscle loss, fatty liver disease and diabetes.
“You know yoyo dieting -- what we call chronic weight instability -- also raises your risk forbad health outcomes.”
Doctors say adults should do 150-300 minutes of moderate intensity physical activity or 75-150 minutes of vigorous exercise each week, but the study authors say just getting off the couch, taking short walks can be beneficial.
Meanwhile, UVA scientists say they have identified 14 genes that can cause weight gain in humans and three that prevent it. That paves the way for treatments that could help people to stay slim.