The Science of Yo-Yo Dieting: Could It Be Worse Than Just Staying Fat?

The term “yo-yo dieting” was first coined by Dr. Kelly Brownell of Yale University in the 1980s and it’s something most women are still all too familiar with even now, almost 30 years later. Some estimates say that as many as 80% of all successful dieters gain back all the weight they lost, plus some, within two years. So as hard as losing weight is it seems keeping it off is even harder. And although small ups and downs are normal (10 lbs or less), weight cycling of 10lbs or more at a time can be very detrimental to your health.

Yo-yo dieting slows your metabolism. When you go on a very strict diet you lose both fat and muscle, but when you regain the weight quickly it comes back on as just fat. And since fat doesn’t burn as many calories as muscle does your metabolism will be slower than it was before. The more times you yo-yo the slower your metabolism gets.

Science shows women who yo-yo more than 5 times over their lifetime usually experience heart damage.

The immune system takes a hit after weight cycling and women who yo-yo have fewer ‘killer cells’ than those who don’t. Killer cells are responsible for fighting infection and fending off cancer in its earliest stages.

So is yo-yo dieting worse than just staying overweight? Experts say no. Although it’s unhealthy to weight-cycle it’s worse to be obese. The best choice is to avoid overly strict diets and weight loss techniques that you won’t be able to maintain, and instead focus on making healthy, lifelong lifestyle changes that will encourage slow but steady weight loss that will last for the long haul.