Dispatch · June 27, 2026 · 8 min read

GLP-1 and Testosterone: The ENDO 2026 Findings Every Man Should See

For millions of men taking GLP-1 medications, a lingering question just got a definitive answer. Research presented at ENDO 2026 — the Endocrine Society's annual meeting in Chicago — confirms that these medications do not suppress male hormones. In fact, they may actually raise testosterone levels in men whose low T is caused by excess weight.

This is the most comprehensive evidence on GLP-1s and male hormones to date, and the implications for men's health are significant.

The Warwick Study: What They Found

Scientists at University Hospitals Coventry and Warwickshire and Warwick Medical School conducted a systematic review of five randomized controlled trials — the gold standard of clinical evidence — comparing GLP-1 medications to other treatments or placebo in men aged 18 to 65.

The findings across all five trials were consistent: GLP-1 medications have no negative impact on reproductive hormones, sexual function, or sperm quality.

But the data went further than "no harm." In specific populations — particularly men with obesity-related low testosterone — the results were actively positive.

Testosterone Went Up, Not Down

A 24-week semaglutide trial showed improvements in sperm morphology and cholesterol levels while keeping testosterone and hormone levels stable. In men with obesity and low testosterone, a 16-week liraglutide study demonstrated that participants experienced increases in testosterone and related reproductive hormones — and their overall health outcomes were better than with testosterone replacement therapy alone.

This matters enormously because TRT, while effective for raising testosterone, has a well-documented side effect that many men don't learn about until it's too late: it can shut down sperm production, sometimes permanently. GLP-1 medications address the root cause — excess fat driving hormonal suppression — without introducing external hormones.

The 53-to-77 Percent Jump

Building on earlier ENDO 2025 data, where researchers tracked 110 men using GLP-1 therapy over 18 months, testosterone normalization rates climbed from 53% at baseline to 77% by study end. These men received no testosterone supplementation. They lost weight — especially visceral fat — and their hormones followed.

Why This Changes the Conversation

For years, the default medical response to low testosterone in overweight men has been TRT. The ENDO 2026 data suggests a better first step: treat the obesity with GLP-1 medication, monitor testosterone levels, and consider TRT only if levels don't normalize with weight loss.

This approach preserves fertility, avoids the side effects of exogenous testosterone, and addresses the underlying metabolic dysfunction driving the hormone deficit. The Endocrine Society's findings represent a fundamental shift in how clinicians should approach low testosterone in men with obesity.

What This Means for You

If you're a man with excess weight and low testosterone, GLP-1 medications may address both problems simultaneously. The ENDO 2026 data suggests that weight loss through GLP-1 therapy can restore testosterone naturally — without the fertility risks and side effects of hormone replacement.

Ask your provider to check your total and free testosterone levels before starting treatment, then again at 3 and 6 months. Many men are seeing meaningful improvements by the 12-week mark.