New research shows that popular anti-obesity medications could do more than just help men lose weight—they may also help bring testosterone levels back to normal.
The study, presented at ENDO 2025, the Endocrine Society’s annual meeting in San Francisco, suggests that these medications could improve both physical health and reproductive health in men with obesity or type 2 diabetes.
Testosterone is a vital hormone in the male body. It supports sex drive, energy levels, bone strength, muscle mass, fat distribution, and red blood cell production.
When testosterone levels drop—which often happens with weight gain or diabetes—men may experience fatigue, lower libido, and an overall decline in quality of life.
While previous research has shown that lifestyle changes and weight-loss surgery can increase testosterone, the effect of anti-obesity medications hasn’t been studied as closely.
Dr. Shellsea Portillo Canales, an endocrinology fellow at SSM Health St. Louis University Hospital, led the new study to explore this link.
Her team reviewed the medical records of 110 adult men who were taking weight-loss medications such as semaglutide, dulaglutide, or tirzepatide. These men had obesity or type 2 diabetes and were not taking testosterone or other hormone treatments. Researchers tracked their testosterone levels over an 18-month period while they were using these medications.
The results were promising. As the men lost weight—on average, about 10% of their body weight—the percentage of those with normal testosterone levels increased from 53% to 77%. This shows a strong connection between these medications and improved hormone levels.
“These findings are exciting,” said Dr. Portillo Canales. “They show that weight-loss medications can also support men’s reproductive health, not just help with weight and blood sugar control.”
This new insight gives doctors and patients more reasons to consider anti-obesity medications, especially for men who may be struggling with low energy or sexual health issues linked to low testosterone.
While more research is still needed, this study adds to the growing understanding that managing obesity can lead to a wide range of health benefits—including restoring hormones that affect mood, strength, and intimacy.
