How Yo-Yo Dieting Really Affects Your Body

You start your health journey in a dramatic way, by significantly changing your diet — maybe choosing a trendy option that’s all about big weight loss in a short time. And it works. But once you start trying to find some balance, the scale creeps back up until you might be where you started, or worse, you’ve gained a little more. So, back on the cycle you go, again and again.

This process is very familiar — and very frustrating — to many people who’ve tried to lose weight. Often called yo-yo dieting or weight cycling, this up-and-down phenomenon of loss and gain can be tough on your confidence, self-esteem and clothing budget. It may also be detrimental to your body in a number of ways.

Here are three of the top issues yo-yo dieting can cause:

In findings presented at a recent American Heart Association meeting, researchers from Columbia University presented evidence that weight cycling has an effect on seven heart disease risk factors: smoking status, weight, diet, physical activity, cholesterol, blood pressure and blood glucose.

As little as 10 pounds of loss-regain-loss can increase risk, according to lead researcher Dr. Brooke Aggarwal, assistant professor of medical sciences at Columbia University Vagelos College of Physicians and Surgeons.

“We think it’s possible that every time the weight is regained, cardiovascular risk factors such as blood pressure, cholesterol and glucose nudge higher, above the baseline level,” she says.

That’s because weight that is lost is usually a mix of fat and some lean muscle tissue, she adds, but weight that is regained is all fat. That’s a big problem, because it’s often in the belly region, and abdominal fat has been strongly associated with risk for cardiovascular disease,

“The findings in our current study suggest that maintaining a consistent weight may be important for managing cardiovascular health, just as achieving a healthy body weight is,” she says.

When you’re on the weight-cycling track, your metabolism kind of freaks out. When that happens, it fights back with increased hunger and slower calorie burn as a way to slow your progress. That’s because your metabolism likes to maintain a “set point,” says Dr. Nicole Harkin, attending cardiologist at Manhattan Cardiovascular Associates.

“This downregulation of the basal metabolic rate, known as adaptive thermogenesis, can persist for some time, with recent research indicating it can last for years,” she notes. “We don’t yet know what exactly determines that set point, and more importantly, how to reset it.”

What they do know, she adds, is yo-yo dieting can cause metabolic damage over time, especially if you cycle up and down repeatedly. The good news is it doesn’t have to be permanent. There are ways to support your metabolism through slower, steady weight loss and also through more strength training, since the amount and density of your muscle mass can affect metabolism function.

Big swings in weight don’t just cause the scale to bounce around, they can also cause hormonal changes that lead to a ripple effect, according to Candice Seti, licensed clinical psychologist, certified personal trainer and certified nutrition coach, known as The Weight Loss Therapist.

Although factors like age and gender can play a part, yo-yo dieting can throw off regulation of hormones like cortisol and melatonin, Seti notes, making it easier to gain the weight back. And the more you weight cycle, the more damaging it becomes as your body tries to adjust.

“That’s why the more you yo-yo, the faster you regain the weight on your next attempt,” says Seti. “Your body is trying to get your hormones back on track, so it causes intense food cravings and holds on to fat as a way to re-find its ‘normal’ operation.”

Dropping significant weight quickly might be good for Instagram, but it’s tough on the body, and fortunately, it’s not the only option. As difficult as it might be to feel patient during the weight-loss process, the common advice of losing just 1–2 pounds per week through long-term changes can be your best bet for keeping the weight off for good, Seti says.

In addition to following a non-trendy diet, there are tried-and-true tactics that can help, such as getting enough sleep, focusing on de-stressing tactics, eating enough protein and tracking your progress on an app like MyFitnessPal.

In terms of exercise, HIIT workouts and strength training can help create a metabolic boost, according to Seti, making your body burn calories for 24–48 hours after a workout.

“Although it’s tempting to lose a lot of weight quickly, yo-yo dieters know that it can be challenging physically and emotionally when the weight starts to come back,” Seti says. “Instead of seeing your body as an enemy you need to fight, work on supporting it in a way that keeps it fueled with healthy foods, plenty of movement, sleep and joy. That sets up great habits that help you drop the yo-yo.”