While gradual weight loss has proven health benefits, cyclical regaining and losing weight comes with health dangers.

© Peter Dazeley | Getty Images

We live in a diet culture, one in which we are constantly exposed to the “next best way to weight loss.” If you’ve toyed with trying one of these trends on for size—Keto, Vegetarian, Atkins, Whole30—or if you’re the type who just dives right in, you likely already know that diets don’t work, at least not for the long term. By their very nature, weight loss diets are usually unsustainable. This is the unfortunate of weight loss diets: weight comes off somewhat quickly in the short-term, the person goes stops following the diet, and the weight is regained (and then some). Repeat. This is yo-yo dieting. This constant fluctuation in weight—over and over again—can potentially be harmful to your health.

The Yo-Yo Effect

Like a yo-yo repeatedly moving up and down, “yo-yo dieting”, also known as the yo-yo effect or weight cycling, describes the up-and-down cyclical pattern of losing weight, gaining it back, then dieting to lose it again. The term was coined in the 1980s by Kelly Brownell of Yale University, but its history is as long as dieting. Weight cycling is as common as weight loss diets, which have become increasingly popular (and problematic) in recent decades—and all genders and ages are impacted. Research suggests somewhere between 20% to 35% of men and 20% to 55% of women have experienced weight cycling. Part of the problem with these figures is the many ways it is defined. Variations occur in the number of cycles of weight loss attempt, across what amount of time, and the amount of weight lost and regained.

Because people with overweight or obesity are more likely to attempt weight loss, they are more exposed to and perhaps prone to weight cycling, compared to someone of normal weight. More and more, research shows that normal weight and even underweight people are affected too, as the desire for losing weight becomes more prevalent. Young girls and teenagers, as well as older women are increasingly preoccupied with weighing less. Excessive weight loss could be a health threat for these groups.

Dangers of Yo-Yo Dieting

Safe and gradual weight loss has documented and well-established health benefits for people with overweight and obesity, such as helping to reduce blood pressure, cholesterol and triglyceride levels, and reducing the risks of diabetes and heart disease. But, repeated and cyclical weight loss-regain-and loss is associated with potential health issues, including the development of disordered eating or eating disorders, type 2 diabetes, hypertension, cancer, bone fractures, and increased mortality. Researchers continue to debate the long-term health consequences of weight cycling.

More Weight Regained. When a person loses muscle mass and fat mass through dieting, there is often a concurrent increase in appetite as the body adapts to conserve energy. This is a protective mechanism that the body uses to protect itself during times of lower caloric intake. Research supports this, as short-term dieters regain about 33% to 65% of lost weight in a year, and one in three of those dieters ends up heavier than they were before the diet.

Hard on the Heart. Research shows that weight cycling can lead to potential fluctuations in cardiovascular risk factors, such as blood pressure, heart rate, and cardiac workload during weight gain. The risk factors make the heart work harder, which may not be eased during weight loss and could contribute to injury. Although studies have shown increased risk for cardiovascular disease and death with weight fluctuations, other studies have shown no significant association. However, in individuals with coronary artery disease, weight fluctuation was associated with higher mortality and higher rate of cardiovascular events independent of traditional cardiovascular risk factors.

Diabetes Danger. Though there is an association between weight cycling and development of type 2 diabetes, the evidence is conflicting and inconclusive. It has been linked with higher-than-normal insulin in the blood, as well as insulin resistance, both of which can be early signs of diabetes. Studies have shown increased risk of diabetes whereas others have noted no significant association.

Why Yo-Yo Dieting Continues

As a society that is increasingly exposed to social media with its pressures of perfection, especially related to physical appearance and weight, it’s no wonder so many people look to diets as a solution. Choosing a diet that is too restrictive to be sustainable may result in rapid weight loss, and short-term feelings of satisfaction. With the weight loss goal achieved, the diet is “done”—until the person returns to their normal eating habits, which inevitably contributes to a weight regain.  And so, the cycle begins.

Diets will not lead to long-term success, but lifestyle changes will. Gradual and consistent weight loss that is not overly restrictive can help people keep weight off and maintain a healthy weight over time.

Yo-yo dieting is a vicious cycle that can be hard to escape. It can be frustrating, defeating, and can threaten long-term health. Reframing the practice of short-term dieting for quick weight loss with healthy lifestyle changes that bring about gradual and sustainable weight loss and maintenance can help break free from this cycle.