Yes, on average, and by less than many headlines suggest. The largest dataset so far, presented at the American Urological Association's 2026 meeting, found that men on semaglutide or tirzepatide saw their median total testosterone rise by roughly 100 ng/dL. That is enough to move some men out of the low range. It is not the same thing as treating hypogonadism.
Independently researched · Educational information, not medical advice · Affiliate disclosure
Updated 7 October 2026. An earlier version of this article said GLP-1 drugs raise testosterone by "100 to 400 ng/dL" and that the effect is purely a side effect of fat loss. The study it described reports neither; the figures below are taken from the study's reported results.
What the 2026 AUA study found
Researchers at Mayo Clinic (Guillén-Lozoya et al., AUA 2026, abstract PD26-01) looked back through health records of men with obesity who were prescribed semaglutide or tirzepatide between October 2018 and October 2025 and had testosterone measured before and after treatment.
| Result | |
|---|---|
| Men with paired total testosterone results | 1,629 |
| Men with paired free testosterone results | 1,216 |
| Median total testosterone, before → after | 320 → 419 ng/dL |
| Median free testosterone, before → after | 9.0 → 10.4 ng/dL |
| Increase in total testosterone after adjusting for age and BMI | median 97.6 ng/dL |
Two findings matter for anyone weighing GLP-1 against TRT:
- The rise held after adjusting for age and BMI. In the authors' words, changes in testosterone "were not directly correlated with BMI reduction alone." Weight loss is probably part of it, but not the whole explanation.
- The typical man ended near the bottom of the normal range. A median of 419 ng/dL sits above the common 300 ng/dL threshold for low testosterone, but well below where many men on TRT are dosed.
It is a retrospective records study, not a randomised trial. Men were tested when their doctors chose to test them, and there was no comparison group, so it shows an association, not proof of cause, and it can't tell you what will happen to you.
Why GLP-1 drugs may raise testosterone
The usual explanation runs through body fat:
- Fat loss. In the STEP 1 trial, semaglutide 2.4 mg weekly produced a mean body-weight change of −14.9% at 68 weeks. In SURMOUNT-1, the mean weight change with tirzepatide was −15.0% (5 mg) to −20.9% (15 mg) at 72 weeks.
- Less aromatase. Fat tissue converts testosterone into estradiol. Less fat means less conversion.
- Better insulin sensitivity and less inflammation, both of which suppress the pituitary signals (LH and FSH) that tell the testes to make testosterone.
The AUA finding that the rise isn't fully explained by BMI change suggests something beyond these three steps may be involved. The authors call it likely multi-factorial; nobody has pinned it down yet.
GLP-1 vs TRT for low testosterone
| TRT | GLP-1 (semaglutide, tirzepatide) | |
|---|---|---|
| What it does to testosterone | Replaces it directly; levels are set by the dose | Typical rise of about 100 ng/dL in the AUA data, varies by person |
| Who it can help | Any man with confirmed hypogonadism | Mainly men with obesity; the AUA data covers only men with obesity |
| Speed | Levels rise within days; symptoms usually improve over weeks | Measured over months of treatment |
| Fertility | Suppresses sperm production (HCG is sometimes added to offset this) | Not known to suppress it |
| Primary purpose | Treating hypogonadism | Weight loss and blood-sugar control |
| Prescription needed | Yes | Yes |
Neither replaces the other. A GLP-1 drug is prescribed for weight or diabetes; any testosterone rise is a welcome extra, not the indication. TRT is prescribed for low testosterone that is confirmed on repeat morning labs.
When each makes sense
These are the questions to bring to a clinician, not a decision tree to follow on your own:
GLP-1 first, then recheck testosterone, may make sense when:
- you have obesity and testosterone is only modestly below 300 ng/dL;
- you were going to treat your weight anyway;
- you want to keep natural production and fertility, at least for now.
TRT is more likely the answer when:
- testosterone is well below the normal range on repeat morning labs;
- the cause is testicular or pituitary (primary or secondary hypogonadism), not weight;
- symptoms are significant and you can't wait months to see whether levels recover.
Both together is something some clinicians do for men with obesity and confirmed hypogonadism. If you're already on TRT, a GLP-1 drug won't raise your testosterone further, since the dose sets it, but weight loss may lower estradiol.
Retest after several months of meaningful weight loss before starting or changing TRT, and use fasting morning labs: testosterone varies through the day.
If you decide on TRT
Online TRT clinics differ more on price structure (what's bundled, labs, contract terms) than on the medication itself. Our clinic rankings score clinics on the same five criteria, cheapest TRT sorts them by published monthly price, and how to choose an online TRT clinic covers what to check before you sign up. We don't recommend clinics for GLP-1 weight-loss treatment on this site.
FAQ
Does GLP-1 raise testosterone in men without obesity? We don't know. The AUA study only included men with obesity, and most earlier studies did too.
How much does GLP-1 raise testosterone? In the largest dataset so far, median total testosterone went from 320 to 419 ng/dL; after adjusting for age and BMI, the median increase was 97.6 ng/dL. Individual results vary widely.
Is the testosterone rise just from weight loss? Not entirely, according to the AUA 2026 study: the change was not directly correlated with BMI reduction alone. Weight loss is still likely part of it.
Can GLP-1 replace TRT? For some men with obesity and borderline-low testosterone, levels may recover enough that TRT isn't needed. For men with clearly low testosterone, or a testicular or pituitary cause, it isn't a substitute.
Does a GLP-1 drug raise testosterone if I'm already on TRT? Not meaningfully: on TRT your level is set by your dose. Weight loss may still lower estradiol.
Related reading
Sources: Guillén-Lozoya AH, et al., "Testosterone levels improve in men under GLP-1 receptor agonist therapy", AUA 2026, abstract PD26-01, as reported by Doximity Op-Med (26 May 2026); Wilding et al., N Engl J Med 2021 (STEP 1); Jastreboff et al., N Engl J Med 2022 (SURMOUNT-1). Medical disclaimer: this article is for informational purposes only and is not medical advice. TRT and GLP-1 receptor agonists are prescription treatments with their own risks; talk to a licensed clinician before starting either. Affiliate disclosure: TRT Picks may earn a commission if you sign up with some clinics through links on this site, at no extra cost to you. This never affects our scores. See our affiliate disclosure and editorial policy.
