Many people are now using weight-loss drugs to help manage obesity and improve their health. One of the most popular medicines is semaglutide, a drug sold under brand names such as Ozempic and Wegovy.
The medication has become widely known because it can help people lose a large amount of weight by reducing hunger and helping them feel full for longer after eating. Doctors also use it to help control blood sugar levels in people with type 2 diabetes.
But while these medicines can lead to major weight loss, scientists are becoming more interested in what kind of weight people are actually losing. Losing body fat is usually considered positive for health, but losing too much muscle can create new problems, especially for older adults.
A recent study found that some people taking semaglutide may lose a greater amount of muscle during weight loss.
The research suggests that women, older adults, and people who do not eat enough protein could face a higher risk of losing lean body mass, which includes muscle.
The study was led by Dr. Melanie Haines from Massachusetts General Hospital and Harvard Medical School. She explained that muscle is extremely important for overall health.
Muscle helps the body control blood sugar, supports movement and balance, protects bone strength, and helps people stay physically independent as they age. When people lose too much muscle, they may become weaker and more vulnerable to health problems later in life.
Researchers have known for years that muscle loss often happens during weight loss. This can occur after strict dieting, surgery, or the use of weight-loss medications. However, scientists are still trying to understand how serious the problem may be for people using newer GLP-1 drugs such as semaglutide.
Semaglutide works by copying the effects of a natural hormone called GLP-1. This hormone helps regulate appetite and digestion. The drug slows stomach emptying and sends signals to the brain that reduce hunger. As a result, many people eat less food without feeling as hungry as before.
Although this can help people lose weight successfully, eating less food may also reduce protein intake. Protein is important because the body uses it to maintain and repair muscles. Without enough protein, the body may break down muscle tissue during weight loss.
To better understand this issue, the research team studied 40 adults living with obesity over a period of three months. Twenty-three participants were prescribed semaglutide, while 17 followed a lifestyle and nutrition program called Healthy Habits for Life, also known as HHL. The researchers measured changes in body weight and lean mass during the study.
The results showed that people taking semaglutide lost more total weight than those in the lifestyle program. However, in both groups, around 40 percent of the weight lost came from lean body mass rather than fat alone.
This means muscle loss appears to be a common part of weight reduction, regardless of whether weight loss comes from medication or lifestyle changes.
The researchers then looked more closely at which participants lost the most muscle. They found that women and older adults in the semaglutide group tended to lose more lean mass compared to others. Lower protein intake was also linked to greater muscle loss.
Another important finding involved blood sugar control. Participants who lost more muscle showed smaller improvements in HbA1c levels, a blood test commonly used to measure long-term blood sugar control. This result may be especially important because semaglutide is often prescribed not only for obesity, but also for diabetes management.
The findings suggest that preserving muscle during weight loss may help people gain more health benefits from the medication. If muscle loss reduces improvements in blood sugar control, doctors may need to pay closer attention to nutrition and muscle health while patients are using GLP-1 drugs.
Dr. Haines believes one possible solution could be increasing protein intake during treatment. Eating enough protein may help the body maintain muscle while still allowing fat loss to occur. She said future research is needed to identify the best ways to help patients lose fat while protecting muscle.
Experts also believe exercise could play an important role. Strength training and resistance exercises are known to help maintain muscle mass during weight loss. Combining proper nutrition, exercise, and medical treatment may eventually become the best strategy for people using these medications.
The study adds to growing discussions about the long-term effects of modern weight-loss drugs. While semaglutide has helped many people improve their health and reduce obesity-related risks, researchers say it is important to understand both the benefits and the possible downsides.
As the use of GLP-1 medications continues to rise around the world, doctors may increasingly focus not only on how much weight people lose, but also on how they lose it. Protecting muscle may become just as important as reducing body fat, especially for women and older adults who may be more vulnerable to weakness and frailty.
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 about a simple path to weight loss, and results showing a non-invasive treatment for obesity and diabetes.
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