GLP-1 Medications Can Increase Testosterone Levels in Men With Obesity

Glucagon-like peptide-1 (GLP-1) anti-obesity medications can improve testosterone levels and health outcomes in men and women diagnosed with obesity or type 2 diabetes (T2D), according to new study data. The results, presented by researchers at the Endocrine Society’s 2025 annual meeting, emphasize the essential impact of testosterone on an individual’s bone mass, fat distribution, muscle mass, strength, and red blood cell production.¹

Image credit: jarun011 | stock.adobe.com

“While it is well known that weight loss from lifestyle changes or bariatric surgery increases testosterone levels, the impact that anti-obesity medications may also have on these levels has not been widely studied,” Shellsea Portillo Canales, MD, endocrinology fellow at SSM Health St. Louis University Hospital, said in a news release. “Our study is among the first to provide compelling evidence that low testosterone can be reversed with the use of commonly prescribed anti-obesity medications.”¹

GLP-1s and Testosterone's Role in Weight Management

GLP-1s improve the management of glucose levels in individuals with T2D, and some are also approved to treat obesity. Commonly used GLP-1s that are FDA approved for weight management include semaglutide (Ozempic; Novo Nordisk), dulaglutide (Trulicity; Eli Lilly and Company), and tirzepatide (Mounjaro; Eli Lilly and Company), which is a GLP-1 and gastric inhibitory polypeptide (GIP) receptor agonist.²

The medications work by triggering insulin release from the pancreas to lower blood glucose, blocking glucagon secretion to prevent further glucose increase, slowing stomach emptying to reduce post-meal glucose absorption, and increasing satiety by influencing brain regions that process hunger.²

Sufficient testosterone levels are reported to help individuals maintain muscle mass and ultimately increase the number of calories that are burned when physically active. Individuals with obesity, specifically men, have a 30% lower testosterone level compared to those who are at a normal weight. Additionally, more than 70% of men who are morbidly obese experience testosterone deficiency that is associated with an abnormally low level of the hormone.³

Analysis of Testosterone on Weight Management

To further the research on why adequate levels of testosterone aid weight management, researchers conducted a study including electronic health records from 110 men with an average age of 54 years who have obesity and T2D. The individuals were using weight loss treatment, including semaglutide, dulaglutide, or tirzepatide, and were not using testosterone or hormonal therapy.^1,4

The researchers measured individuals total and free testosterone levels at the beginning and during the 18-month treatment. The results demonstrated that men on weight loss medications had a 10% weight reduction, which was accompanied by a 53% to 77% testosterone increase.^1,4

“Results from this study show that there is a direct correlation between the use of anti-obesity medications and testosterone levels,” Portillo Canales concluded in the news release. “Doctors and their patients can now consider this class of medications not only for the treatment of obesity and to control blood sugar, but also to benefit men’s reproductive health.”¹

REFERENCES

1. Anti-obesity medications can normalize testosterone levels in men. EuerkAlert!. News release. July 14, 2025. Accessed July 18, 2025. https://www.eurekalert.org/news-releases/1090292

2. Cleveland Clinic. GLP-1 Agonists. News release. Updated July 3, 2023. Accessed July 18, 2025. https://my.clevelandclinic.org/health/treatments/13901-glp-1-agonists

3. Can Boosting Your Testosterone Help You Lose Fat? Healthline. News release. June 13, 2023. Accessed July 18, 2025. https://www.healthline.com/nutrition/testosterone-and-fat-loss

4. Health Rounds: GLP-1 obesity drugs may boost low testosterone. Reuters. News release. July 16, 2025. Accessed July 18, 2025. https://www.reuters.com/business/healthcare-pharmaceuticals/health-rounds-glp-1-obesity-drugs-may-boost-low-testosterone-2025-07-16/