Yo-Yo Dieting Not Linked to Cancer Risk

The "yo-yo diet," also known as "weight cycling," a form of extreme dieting which entails the cyclical and repetitious loss and gain of body weight, has not been associated with the risk for all cancer and 15 individual cancers according to the American Cancer Society.

In a new study published in the American Journal of Epidemiology, a team of American Cancer Society researchers led by Victoria Stevens has some reassuring words to share. "For the millions of Americans struggling to lose weight, the last thing they need to worry about is that if it comes back, they might raise their risk of cancer.

"This study, to our knowledge the largest and most comprehensive to date on the issue, should be reassuring. Our findings suggest that overweight and obese individuals shouldn't let fears about their ability to maintain weight loss keep them from trying to lose weight in the first place."

For the study, Stevens and her team examined the correlation between weight cycling and cancer among more than 132,000 men and women enrolled in the Cancer Prevention Study II Nutrition Cohort over a 17-year period.

Of them, more than 25,000 developed cancer during study period. All participants were asked how many times in their lives they had intentionally lost at least 10 pounds and then regained that weight. Of the total number of participants, 57 percent of women and 43 percent of men reported that they did.

The incidence of cancer among those who admitted to weight recycling was then compared with those who did not yo-yo diet. The research team failed to find any significant causal connection between risk of cancer and yo-yo dieting.

Weight cycling is fairly common in America, where 68.5 percent of adults and 31.8 percent of children and adolescents are considered overweight or obese. And obesity is associated with increased risks of cancer according to the National Cancer Institute.

But trying to lose too much weight too soon by undergoing some extreme form of fad dieting usually won't work either. The weight loss will just be regained the moment the dieter starts attempting to eat normally again. Then the dieter seeks to shed off the regained weight. Then another cycle begins. 

People caught up in the weight loss and regain cycle, aside from the depression, frustration and fatigue that they typically feel following their inability to hold on to their ideal weights, are also usually apprehensive that they are putting themselves at risk of even bigger health issues.

They are afraid they may have messed up with their metabolism. Now, they need not, at least as far as risk of cancer is concerned.

Based on the said study, "they should keep trying to lose weight even though they may not maintain the weight," Stevens told Today. "It's better to go ahead and try... rather than just being worried that there's going to be something bad happening if you don't maintain the weight loss and not trying at all."