It’s a well-known tale: A large percentage of those who lose weight end up gaining it all back—and often more. For a long time, it was assumed that this was because dieters lapse back into the eating habits that caused them to gain weight in the first place. But over the past several years, there have been a series of studies showing that there is something else at work.
People who have lost weight experience long-term changes in their metabolism that make it extremely difficult to maintain that weight loss, even when they are vigilant about maintaining healthy eating habits. Their bodies simply burn fewer calories than those who have never been overweight.
The result is yo-yo dieting, where people repeatedly lose and gain and lose the same 40 or 50 pounds many times over the course of their lives. Not only is this frustrating, it’s actually dangerous. Yo-yo dieting is hard on your heart and increases the risk of various diseases.
However, some new research done at the Weizmann Institute of Science in Israel sheds some light on what might be going on—and how we might be able to stop the cycle.