Many people are turning to new weight-loss drugs like semaglutide to help manage obesity. These medications have shown powerful effects in helping people shed extra weight.
However, a new study suggests there may be an unexpected side effect—especially for women and older adults.
They might be losing not just fat, but also important muscle. Thankfully, eating more protein might help stop this from happening.
Semaglutide is part of a newer class of drugs that help control blood sugar and support weight loss. It works by mimicking a natural hormone in the body that helps people feel full. As a result, people eat less and lose weight.
It has been praised for helping those with obesity or diabetes reach healthier body weights. But while it helps people slim down, there’s growing concern about what kind of weight is being lost.
Doctors and scientists know that when people lose weight, they often lose both fat and muscle. Losing fat is good for health, but losing muscle can be harmful. Muscle is important because it helps people move, stay strong, and keep their balance. It also helps control blood sugar levels and supports healthy bones.
If someone loses too much muscle, they might become weaker, have trouble staying active, and be more likely to fall or feel tired. Over time, losing muscle can even lead to a condition called frailty, which makes it hard to recover from illness or injury.
A new small study from researchers at Massachusetts General Hospital and Harvard Medical School looked at how semaglutide affects muscle in people with obesity. The study included 40 adults.
Some of them were given semaglutide for three months, while the rest followed a diet and lifestyle program called Healthy Habits for Life. Both groups lost weight during the study, but those taking semaglutide lost more.
The researchers found that about 40% of the weight lost from semaglutide was not fat—it was lean mass, which includes muscle. That’s a big concern.
Even more importantly, people who were older, women, or ate less protein were more likely to lose muscle. And among those taking semaglutide, losing more muscle was linked to less improvement in their blood sugar levels.
This means that losing muscle could reduce some of the health benefits of the drug. Semaglutide is supposed to help people with obesity not only lose weight but also improve their blood sugar and reduce the risk of diabetes. But if too much muscle is lost, those benefits might not be as strong.
The good news is that eating more protein seems to help protect muscle while using semaglutide. Protein is a key nutrient that helps build and repair muscle. Getting enough protein from foods like meat, fish, eggs, beans, or dairy might help people lose fat while keeping their muscles strong.
The lead researcher, Dr. Melanie Haines, says that doctors need to be aware of this risk when prescribing semaglutide, especially for older adults and women. More research is needed to find the best way to help people lose weight safely.
Scientists want to figure out how to make sure people lose fat but keep their muscles. This could involve eating more protein, doing resistance exercise, or combining the drug with other treatments.
In summary, semaglutide is a powerful tool for weight loss, but it’s not perfect. Losing muscle can be a hidden problem, especially for women and older adults. Eating more protein may help prevent this.
As more people use weight-loss drugs, doctors and patients need to think about more than just the number on the scale—they need to make sure the weight being lost is mostly fat, not muscle.
If you care about obesity, please read studies about Scientists find new key cause of obesity and findings of Double whammy: diabetes drug also knocks out obesity.
For more about weight loss, please read studies about Scientists find secrets to long-term weight loss success and findings of Weight loss surgery linked to this mental disease.
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