A widely used weight-loss drug may have an unexpected side effect, especially for women and older adults. New research suggests that people taking semaglutide could lose more muscle than expected while losing weight. However, scientists say that eating more protein may help protect the body from this problem.
Semaglutide is a medication used to treat obesity and type 2 diabetes. It works by copying the action of a natural hormone in the body that controls appetite and digestion.
This hormone helps people feel full sooner and stay full longer, which leads to eating less food and losing weight. Because of its effectiveness, the drug has become very popular worldwide as a treatment for obesity.
While losing weight can improve health, it is not always just body fat that disappears. The body can also lose muscle, which doctors call lean mass. Muscle is important for strength, balance, and movement.
It also helps control blood sugar and supports healthy bones. Losing too much muscle can lead to weakness, higher risk of falls, poor metabolism, and loss of independence in older adults.
The study was presented at ENDO 2025, a major meeting of hormone experts. Researchers followed 40 adults with obesity for three months.
Twenty-three participants were treated with semaglutide, while the others followed a structured lifestyle program that focused on healthy eating and habits. The scientists measured changes in body weight and muscle mass during the study period.
People taking semaglutide lost more weight overall compared with those in the lifestyle program. However, in both groups, about 40 percent of the weight lost came from lean mass, including muscle. This shows that muscle loss is a common part of weight loss, no matter how the weight is reduced.
The researchers also discovered that muscle loss was not the same for everyone. Women, older adults, and people who ate less protein tended to lose more muscle while taking the drug. In addition, people who lost more muscle showed less improvement in their blood sugar levels.
Blood sugar control is often measured using a test called HbA1c, which shows average sugar levels over several months. This result suggests that keeping muscle may help the body respond better to treatment.
These findings are important because semaglutide is often prescribed to improve blood sugar control as well as to promote weight loss. If muscle loss reduces these benefits, doctors may need to consider ways to protect muscle during treatment.
Researchers believe that eating enough protein could be one of the simplest and most effective strategies. Protein is essential for building and maintaining muscle, especially when people are eating less food overall.
Experts also say that strength exercises and regular physical activity may help preserve muscle while losing weight. This is especially important for older adults, whose muscles naturally become weaker with age. Protecting muscle can help maintain mobility, independence, and overall health.
Although the results are important, scientists emphasize that more research is needed. Larger studies over longer periods will help determine the best ways to lose fat while keeping muscle when using medications like semaglutide.
For now, people taking the drug should talk with their healthcare provider about nutrition, exercise, and safe ways to protect their muscle mass during weight loss.
The study highlights an important message: successful weight loss is not only about the number on the scale, but also about maintaining a strong and healthy body. With the right balance of medication, diet, and lifestyle changes, it may be possible to lose weight safely while keeping muscles strong.
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.
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