Yo-yo dieting may pose different risks depending on starting weight

Yo-yo dieting, also known as weight cycling, involves repeatedly losing and regaining weight. A recent study in Nature Reviews Endocrinology suggests that the impact of this weight fluctuation may depend on a person's starting weight. For individuals with obesity, repeated cycles of weight loss and regain seem to have minimal additional negative effects on weight and body composition over time.

However, for people of normal weight, particularly those predisposed to obesity, greater loss of lean body mass (including muscle) and a more significant decrease in resting energy expenditure when losing weight may pose long-term risks. If weight is regained, a larger portion of it may be in the form of fat tissue. This could increase the risk of developing obesity for those predisposed to it.

Social factors and hereditary predispositions may also contribute to weight fluctuations. The rise of effective weight-loss medications has led some people of normal weight, even those not significantly overweight, to seek these treatments outside approved indications. Doctors should carefully weigh the potential benefits and risks of prescribing weight-loss medications, especially for metabolically healthy, normal-weight individuals.

While there is no evidence that repeated weight loss attempts worsen weight trends in people with obesity, further research is needed to confirm these findings and directly compare the long-term effects in both groups.