The Dangers of Yo-Yo Dieting

Weight cycling means losing weight, then regaining it, then repeating the cycle. When this weight loss is the result of dieting, the process is often called “yo-yo dieting.” New studies show that weight cycling contributes to heart disease and earlier death.

The doctors who preach “lose weight” to people with diabetes need to learn the dangers of weight cycling. Their prescriptions for weight loss may be doing more harm than good.


A new study in The New England Journal of Medicine found that, in patients with coronary heart disease (CHD), weight cycling was strongly associated with heart attacks, strokes, and death. Lead author Dr. Sripal Bangalore of New York University reported that the more weight subjects had lost and regained, the greater the risk.

The study reviewed records of roughly 9,500 people with heart disease. The data collection started in 2005. After a year of the study, participants continued to report their weight, among other factors, every six months.

Those whose weight had swung by an average of 8.5 pounds had a 124% increased risk of death, 117% increased risk of heart attack, and 136% increased risk of stroke compared to people whose weight had changed by 2 pounds or less. People with the greatest swings in weight also had a 78% increased risk of diabetes, even after correcting for all traditional risk factors.

The risk of weight cycling has been found before. In the Framingham Heart Study, which has been going on nearly 70 years, people whose weight swung up and down over the years were more likely to die of heart disease and strokes than people with more stable weights.

How weight cycling hurts
Previous studies have shown risk for high blood pressure and high cholesterol among yo-yo dieters.

An article in the International Journal of Obesity reported that weight cycling may contribute to heart and blood vessel disease in several ways. These include high blood pressure, increased fat around the abdominal organs, changes in fatty acid composition, insulin resistance, and increased cholesterol.

Weight cycling leads to changes in heart rate, stress hormones, kidney function, blood glucose, and lipids. These factors can worsen, “with overshoots above normal values during weight regain periods.” The authors say these overshoots “when repeated over time, will stress the cardiovascular system and probably contribute to the overall cardiovascular [risk] of weight cycling.”

Weight regain is normal after weight loss, especially rapid weight loss. An article on quoted experts saying that 95% of those who lose weight rapidly will regain lost weight (and possibly more).

A recent British study of over 170,000 people found that the chances of achieving even a 5% weight loss were 1 in 7 for severely obese women and 1 in 8 for severely obese men. The chances of attaining a normal weight were 1 in 210 for obese men and 1 in 124 for obese women.

Bodies try hard to regain lost weight, because they feel safer with more fat. This happens because, for millions of years, the major threat to survival was not having enough food. Fat protects against famine, so bodies want to keep it.

Metabolism slows down after weight loss, and levels of hunger hormones go up. Food even starts to taste better. Weight cycling is the norm, not an exception. It’s even worse when loss and regain are rapid, as often happens with commercial diet products.

Avoiding the weight cycle
So if you’re heavy and have diabetes, should you try to lose weight? How do you avoid weight cycling?

One rule is not to do anything to lose weight that you won’t be happy doing for the rest of your life. Moving your body more and eating healthier food that you enjoy are good ideas.

Restricting calories and cutting out things you like are usually bad ideas. You probably won’t be able to keep them up, and when you go back to your old ways, your weight will return, with interest.

Linda Bacon, PhD, author of Health At Every Size, says don’t focus on weight at all. It’s not about a number on a scale. It’s about how you live and how you feel, with better physical activity, less stress, and less reliance on artificial foods to make you feel better.

If you do those things, you might find your weight going down, but you’ll be less likely to cycle back. Or your weight may not change, but your health and quality of life will likely improve.

When it comes to managing diabetes, it can take a little bit of “pure magic” to make things work, says Scott Coulter. Bookmark and tune in tomorrow to read more.

  • Maggie York

    Great article, David. Let’s hope clinicians get the message and apply it!

  • Julie Duffy Dillon

    Thank you for this insightful post David. I hope more appreciate that weight loss is not a behavior and pursuing weight loss contributes to physical and emotional dis-ease.