Researchers in Louisiana are delving into the long-term effects of widely used weight loss medications such as Ozempic and Wegovy, focusing on potential drawbacks like muscle loss and a slowed metabolism. These drugs, which mimic a natural hormone to regulate blood sugar and promote fullness, can lead to significant weight reduction, often between 15% and 25% in a year.
Investigating Metabolic Adaptation and Muscle Mass
At the Pennington Biomedical Research Center, Dr. Eric Ravussin is leading studies to quantify how these GLP-1 medications affect muscle mass and to explore methods for preventing a decrease in patients’ metabolic rate. The drugs’ effectiveness in promoting weight loss can sometimes plateau as the body adapts to the reduced calorie intake, a phenomenon known as metabolic adaptation. This survival mechanism can cause the body to become more energy-efficient, hindering further weight loss or even leading to weight regain.
“They have spectacular weight loss,” Ravussin stated, but added that pharmaceutical companies are interested in understanding the drugs’ impact on body composition and energy expenditure. His research will monitor participants’ resting metabolic rate—the calories burned at rest—and muscle mass while they are on the medication. Ravussin noted that a common observation is a significant drop in weight over initial months, followed by a plateau or even regaining weight in subsequent periods, partly due to metabolic slowdown.
To counteract this, Ravussin is experimenting with combining GLP-1s with substances that can boost metabolism, though he stressed this is for research purposes and not a recommendation. He is also examining the impact on muscle mass, an area where public perception may differ from scientific measurement. “The hypothesis is you don’t lose as much muscle as people think because we don’t measure the muscle,” Ravussin explained, emphasizing the need for methods like MRI to accurately assess muscle changes.
Clinical Perspectives on Side Effects
Drake Bellanger, a physician specializing in obesity medicine at Baton Rouge General, frequently addresses patient concerns about GLP-1s, including fears of muscle deterioration. He advises that adequate protein intake and regular exercise can significantly mitigate muscle loss. Bellanger suggests that consuming over 80 grams of protein daily and engaging in resistance training helps maintain muscle mass, leading to minimal loss when combined with these medications.
Bellanger also observes more common short-term side effects, reporting that one to two out of every ten patients experience nausea. The research at Pennington utilizes a specialized metabolic chamber, a sophisticated facility costing millions, to gather precise data on calorie expenditure. Participants will spend extended periods in the chamber to allow for detailed metabolic calculations, both with and without the drugs.
Future Directions for GLP-1 Research
The ongoing studies aim to answer critical questions for the next generation of GLP-1 drugs: how to minimize muscle loss and prevent a substantial drop in resting metabolic rate. Ravussin highlighted that understanding and mitigating these effects are key to optimizing the long-term benefits of these powerful weight loss medications.
Steve Lopez is the Editorial Page Editor for News Raise. He covers Health. He has won more than a dozen national journalism awards for his reporting and column writing at seven newspapers and four news magazines.
