"I Thought I Was Just Losing Weight, But Became a 'Testosterone Man'... Unexpected Effects of Obesity Medications"

US University Research Team Finds
Obesity Medications Effective in Restoring Testosterone

A study has found that obesity medications can help improve health by increasing testosterone levels in men with obesity or type 2 diabetes.

The photo is not related to the specific content of the article. Pexels

According to a preliminary study by a research team at SSM Health, a medical center affiliated with Saint Louis University Hospital, presented at the annual meeting of the Endocrine Society (ENDO 2025) on July 14 (local time), GLP-1-based obesity medications such as semaglutide, dulaglutide, and tirzepatide were shown to be effective in normalizing testosterone levels in men.

Testosterone plays an important role not only in male sexual function, but also in bone density, fat distribution, muscle mass, muscle strength, and red blood cell production. However, increases in body weight and the prevalence of type 2 diabetes can lower testosterone levels, which may lead to fatigue, reduced libido, and a decline in quality of life.

The researchers analyzed the electronic medical records of 110 adult men with obesity or type 2 diabetes. All participants were taking at least one of semaglutide, dulaglutide, or tirzepatide, and none were receiving testosterone or other hormone therapies. Total and free testosterone levels were measured before starting treatment and over an 18-month treatment period.

As a result, these men lost about 10% of their body weight, and the proportion of men whose testosterone levels returned to normal increased from 53% to 77%. This suggests that obesity medications may also have a positive impact on reproductive health in men with obesity or type 2 diabetes.

Dr. Chelsi Portillo Canales, who led the study, explained, "It is well known that weight loss through lifestyle changes or bariatric surgery can increase testosterone levels, but the effects of obesity medications on these levels have not been sufficiently studied. This study is the first to provide strong evidence that commonly prescribed obesity medications can restore low testosterone levels."

Dr. Portillo Canales added, "These findings show a direct link between the use of obesity medications and testosterone levels. Physicians and patients can now consider these drugs not only for obesity treatment or blood sugar control, but also as an option for improving men's reproductive health."