GLP-1 (glucagon-like protein-1) receptor agonists like Wegovy and Ozempic are so popular that their use by an increasing number of Americans desiring their weight loss benefits is leading to shortages and increasing reports of “fake” drugs in the marketplace. These are doubly troublesome for those for whom the medications were initially developed—individuals with type 2 diabetes.
But did you know that despite their popularity and success in promoting weight loss, much of this loss is not just from body fat but also muscle?
Clinical studies have reported that 25-40% of total body weight loss is attributable to muscle loss. Indeed, rapid weight loss with these drugs may decrease your metabolic rate while reducing bone density.
Therefore, when considering these medications for weight loss, the goal should not simply be a reduction in overall weight but also an improvement in body composition with maintenance of your muscle mass. Without preventing muscle loss, the individual may exhibit what has frequently been called “skinny fat.” Being skinny fat may also negatively affect one’s quality of life and energy levels. So, having a lower body weight (even considered “ideal”) does not equate to being healthy.
Benefits of Maintaining Muscle Mass
Skeletal muscle is the largest organ in the human body and accounts for approximately 30-35% of an individual’s total weight. Muscles allow for body movement and provide many physiological functions within the body, not the least being their enrichment in mitochondria (the “battery” of life). The benefits of maintaining muscle mass on overall health and wellness have been noted by many researchers (1). Indeed, having more muscle supports weight loss and maintenance since these tissues are the primary users of the body’s energy (as a result of all those mitochondria). This energy “burning” is even true during rest; when a person loses muscle mass, the resting metabolic rate decreases, too.
Luckily, there are lifestyle and dietary choices that can mitigate lean mass loss during weight loss. Moreover, individuals older than 60 are already more prone to muscle loss and need to be particularly mindful of building muscle and the potential muscle loss effects of GLP-1 medications.
High-Quality Dietary Protein Intake is Essential for Optimal Muscle Status
The dynamic relationship between muscle protein synthesis (MPS) and muscle protein breakdown (MPB) regulates total body muscle mass. Following a meal rich in protein (20-40g), MPS increases ∼2–3 fold, while MPB can be inhibited by ∼50% in young, healthy muscle; however, as noted previously, these effects are further blunted in older individuals and, likely, in those using GLP-1 drugs. Combining high-quality protein intakes spaced throughout the day with exercise (particularly resistance exercise) will reduce MPS and allow for the maintenance of muscular tone. In this context, high-quality proteins are also rich in essential amino acids required for MPS and its signaling to begin synthesis (with the protein’s leucine content being the most important amino acid).
In conclusion, the use of GLP-1 medications has been shown to promote rapid weight loss; however, much of that weight loss is attributed to the loss of muscle mass. By consuming high-quality protein meals or supplements evenly spaced throughout the day, combined with an exercise program, you can minimize the potentially harmful health effects of GLP-1-induced muscle loss.
References:
- Deutz NE, Bauer JM, Barazzoni R, et al. Protein intake and exercise for optimal muscle function with aging: recommendations from the ESPEN expert group. Clin Nutr. 2014;33(6):929-936. doi:10.1016/j. clnu.2014.04.007
