Experts Yo-Yo on Health Benefits of Yo-Yo Diet

Losing weight and gaining it right back again is better for your health than remaining obese, according to a new study in mice.

The findings suggest so-called yo-yo dieting is not as bad for your health as once thought.

Mice in the study that were put on a yo-yo diet lived just as long as mice on a low-fat diet. Mice that ate a high-fat diet, on the other hand, had a shorter lifespan.

Although maintaining a stable, healthy weight is still ideal, "People should not stop trying to lose weight if they are, like I am, a person who gains weight frequently and tries to lose it," said study researcher Edward List, a scientist at Ohio University's Edison Biotechnology Institute.

The study was presented today at the annual meeting of the Endocrine Society in Boston.

Yo-yo dieting

About two-thirds of Americans are overweight or obese, and research has shown many are unable to keep their weight off over the long-term.

List and his colleagues put 30 mice on one of three diets: a high-fat diet, a low-fat diet and a yo-yo diet that fluctuated between high-fat and low-fat for four-week periods.

Animals on the high-fat diet ate more, weighed more, had more body fat and higher blood sugar levels than the mice on the low-fat diet. Mice on the yo-yo diet had these characteristics, too, but only during the high-fat period of their diet. During the low-fat period, they were healthier, the researchers said.

The mice on the low-fat diet and those on the yo-yo diet lived about two years, on average. In contrast, the mice on the high-fat diet lived about 1.5 years.

Weight-loss benefits

The findings agree with other research performed with people, said Dr. Louis Aronne, an obesity expert at Weill-Cornell Medical College in New York City, who was not involved with the study.

"Given what we're learning about obesity and its impact on disease, it makes sense that yo-yo dieting not only doesn’t hurt, but could help," Aronne told MyHealthNewsDaily.

Fat cells produce hormones that can harm the body by increasing inflammation and blood sugar levels. When people lose weight, even for a short time, production of these hormones is reduced as well, he said.

A 2002 study of people at risk for developing diabetes found that a 7 percent weight loss reduced the chance of developing diabetes by 58 percent, Aronne said. Those in the study initially lost 7 percent of their weight, but only maintained a 4 percent weight loss over a four-year period, he said.

"A little bit of weight loss goes a long way when it comes to improving health," Aronne said. "We don't have to get people to their ideal body weight," before they start to see health benefits, he said.

Pass it on: Yo-yo dieting may be better for you than not dieting at all.

This story was provided by MyHealthNewsDaily, sister site to LiveScience. Follow MyHealthNewsDaily staff writer Rachael Rettner on Twitter @RachaelRettner.

Rachael Rettner

Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.