People trying to lose weight often hear warnings about yo-yo dieting.
The common belief is that repeatedly losing and regaining weight permanently harms the body, slows metabolism and makes future weight loss even harder. A new scientific review suggests that this idea may not be backed by strong evidence.
The review was carried out by researchers from the University of Copenhagen and the German Center for Diabetes Research.
Their findings were published in The Lancet Diabetes & Endocrinology after examining many years of research involving both humans and animals.
The scientists looked at studies investigating weight changes, body fat, muscle mass, metabolism and the development of diabetes and cardiovascular disease.
They wanted to find out whether weight cycling itself causes health problems or whether other factors are responsible.
The authors found that many earlier studies did not fully account for ageing, existing illnesses and the amount of time people spent living with obesity. When these important factors were considered, much of the apparent harm linked with weight cycling became much weaker or disappeared.
Contrary to popular belief, the review found no reliable evidence that repeated weight loss permanently damages metabolism or causes people to lose increasing amounts of muscle. Most people who regained weight simply returned to roughly the same body composition they had before losing weight.
The researchers also made an important distinction between losing health benefits and causing new harm. Regaining weight often reverses improvements in blood pressure, blood sugar and cholesterol, but current evidence suggests it does not usually leave people worse off than before they first lost weight.
The review also has implications for modern obesity treatments. New medicines such as GLP-1 receptor agonists can produce impressive weight loss, but many patients regain weight after stopping treatment. The authors believe these periods of improved health should still be viewed as valuable rather than as evidence that treatment has failed.
The researchers encourage doctors to continue supporting patients who are trying to lose weight, even if maintaining the weight loss proves difficult. Repeated attempts should not be seen as harmful, especially if they improve health for months or years at a time.
Although the review offers reassurance, it does not suggest that weight regain is desirable. Keeping a healthy weight remains the best long-term strategy whenever possible. Healthy eating, regular physical activity and ongoing medical support remain important parts of obesity treatment.
Review and analysis: The strength of this publication lies in its careful review of many different studies instead of relying on a single experiment.
While more long-term research is still needed, the findings challenge a common myth and may help reduce unnecessary fear about trying to lose weight. Overall, the evidence suggests that attempting weight loss is likely to provide more benefits than risks, even if some weight is regained later.
If you care about weight loss, please read studies that hop extract could reduce belly fat in overweight people, and early time-restricted eating could help lose weight .
For more health information, please see recent studies that Mediterranean diet can reduce belly fat much better, and Keto diet could help control body weight and blood sugar in diabetes.
Source: University of Copenhagen.
