A relatively common bit of “folk wisdom” says that repeatedly losing and gaining weight — weight cycling — may lead to some negative health risks, including making it harder to lose weight. This myth is becoming an important concern as excess weight is increasingly identified as a major risk for our most common health problems, including heart disease, diabetes and common forms of cancer.
But myths that tie weight cycling to greater regain at the waist or to increased difficulties in future weight loss attempts are unfounded, according to the National Institutes of Health. Research does not support dieting history influencing waistline fat and difficulty losing weight, which both tend to increase with age.
Neither does research offer much support to the fear that weight cycling increases a person’s tendency to regain weight. In a six-year study of healthy men and women ages 20 to 78, weight gain was not related to weight cycling in men. Women weight cyclers, who gained about one pound a year, showed only a slight tendency to gain more weight than those whose weight did not cycle.
Another study followed almost 2,500 obese men and women in a weight reduction program based on a low calorie diet. The program included 480 patients repeating the program for up to the fourth time. Among the 480 patients, there was no difference in rate of weight loss, blood pressure and blood cholesterol whether it was the patient’s first or fourth time through the program.
Worry more about excess weight
Studies have found that excess weight — not weight cycling — strongly increases risk of developing the common type 2 diabetes. A study of more than 46,000 women aged 25 to 43 classified women who had intentionally lost at least 20 pounds or at least 10 pounds three or more times in a five-year period as severe or mild weight cyclers, respectively.
Women who were more overweight were from seven to 63 times (depending on degree of overweight) more likely to develop diabetes than the leanest women. After adjusting for weight, weight cycling was not related to development of diabetes. Women who were most overweight were more likely to have been weight cycling. But that doesn’t mean that weight cycling caused the higher weight; it is just as possible that weight cycling was more common among those who were most overweight at the start.
Cancer risks for the overweight
Research has consistently shown that excess weight increases cancer risk; only a few studies suggest weight cycling may increase risk of certain cancers at all. Being overweight is a strong risk factor for cancers of the colon, endometrium (uterus), breast (after menopause) and more. In a study of more than 10,000 women ages 50 to 79, the most overweight women were much more likely to develop breast cancer.
Weight gain during adulthood increased risk by 8 percent for each 11 pounds gained above the lowest adult weight. Weight cycling was not associated with increased risk. In another study of over 3,000 women, higher body mass index (BMI, which is a measure of weight) was linked with greater endometrial cancer risk.
Women whose BMI was in the top 25 percent had three times the risk of endometrial cancer compared to the leanest women. For each 11 pounds of weight gained, risk of endometrial cancer increased 20 percent. History of weight cycling increased risk 30 percent after adjusting for BMI and other risk factors, but women who lost weight and kept it off reduced risk of endometrial cancer by 30 percent.
Advice to smokers is not to be afraid to try quitting even if earlier attempts were unsuccessful. With excess weight posing so many health risks, the same advice seems appropriate if you want to lose weight, especially if you can learn from past experiences to develop healthy eating and exercise habits you can maintain. Weight cycling is not desirable, but it is not as risky as staying significantly overweight.