- Semaglutide has been widely praised as an effective drug for weight loss and appetite reduction.
- But patients also lose muscle mass, which can sabotage the health benefits, said Dr. Peter Attia.
- He recommends trying other weight loss strategies first and getting enough protein to maintain muscle.
The popular new weight-loss drug semaglutide is helping people lose weight, but it can also cause significant loss of muscle mass, according to a doctor.
Semaglutide has been described as a “game changer” for treating obesity and won FDA approval in 2021 for weight loss under the brand name Wegovy. It's also available as Ozempic, which is the same drug but is sold to treat type 2 diabetes (although doctors can and do prescribe it for weight loss as well).
Semaglutide works by mimicking a natural hormone in the body that helps regulate blood sugar, digestion and hunger.
But the FDA and semaglutide success stories don't take into account patients who are losing lean muscle mass at the same time, which could worsen their health long-term, Dr. Peter Attia said in a recent episode of his podcast “The Drive.”
Body composition, or the ratio of muscle to fat, is a more helpful measure of weight loss (and subsequent health improvements) than sheer pounds lost, Attia says.
Attia also noted that people who do not have type 2 diabetes or a high body fat percentage would want to use the drug to achieve a small amount of cosmetic weight loss.
“Perhaps what disturbs me more are the people who reach out to me who are frankly not overweight but say ‘I really want to lose 10 pounds so I can look good on my vacation and I should Accept this, right?'” he said.
In an earlier post, Attia said his patients on semaglutide lost significant weight, but not all body fat.
“I was shocked by how quickly they lost muscle,” he said.
While some muscle mass is expected during weight loss, losing too much can be counterproductive. Muscle mass is important for a healthy metabolism and preventing injury, especially as we age.
To offset possible side effects, Attia said he recommends semaglutide to patients who have already tried other weight-loss strategies without the drug, emphasizing their need for adequate protein intake and exercise to maintain muscle.
There is some promising evidence that a similar drug called tirzapetide — which is still awaiting FDA approval for weight loss — may be more effective, Attia said.
At the same time, Attia says it's worth remembering the importance of muscle mass to health, not just the number on the scale.
“Ultimately, it's not your weight that matters, but your body composition and fitness,” says Attia.
