A recent study from the University of North Carolina School of Medicine found that weight loss, especially from popular incretin-based medications like semaglutide and tirzepatide, often leads to more muscle loss than expected.

The study was published in the journal Annals of Internal Medicine. It was led John A. Batsis, MD, an expert on obesity and nutrition at the UNC School of Medicine and the UNC Gillings School of Public Health.

The study analysed multiple studies and found that muscle-related tissue accounted for about 35% of total weight lost in incretin groups, exceeding safe benchmarks in two-thirds of cases.

While these drugs help with type 2 diabetes and obesity by lowering appetite and helping in weight reduction, the side effect is lean mass loss.

People with obesity usually have more muscle than normal-weight individuals, however, rapid weight loss reduces it without always preserving strength. In non-drug methods like dieting, muscle loss is around 2-10% for 8-10% body weight loss, but incretins increase the proportion.

For older adults over 60, this can be dangerous as few trials include them. However, muscle loss can increase fall risks, frailty, and poor mobility. Batsis said, "While muscle loss is expected during weight loss, we observed that the proportion of weight loss attributable to muscle was consistently higher than anticipated across studies. 

Source:Ndtv