← Patient EducationTestosterone in men: what the research actually shows.
Testosterone is the most-prescribed hormone in America, and for years the evidence behind it was thin. Since 2016, several large randomized trials have filled the gaps. Here is what they found — benefits, trade-offs and heart safety — in one page.
Reviewed by the Elevate Care Team · Dr. Eric W. Anderson, MD
The headline findings
The largest testosterone trial ever run found no increase in cardiovascular death, heart attack or stroke versus placebo: 7.0% of men on testosterone versus 7.3% on placebo over about three years, meeting the statistical bar for non-inferiority.Lincoff AM et al. New England Journal of Medicine, 2023;389:107–117 (TRAVERSE)
In the NIH Testosterone Trials, 790 men 65 or older with low testosterone and symptoms were treated for one year: sexual activity, sexual desire and erectile function all improved significantly against placebo. Vitality did not.Snyder PJ et al. New England Journal of Medicine, 2016;374:611–624
In the Hypogonadism in Males study of men visiting U.S. primary-care practices, 38.7% had total testosterone below 300 ng/dL — the level trials use to define low testosterone. Many of them had no symptoms, which is why a number alone is not a diagnosis.Mulligan T et al. International Journal of Clinical Practice, 2006;60(7):762–767 (HIM study)
How men differ from women
Men are dosed into the normal adult male range — TRAVERSE adjusted doses to hold testosterone between 350 and 750 ng/dL, roughly ten times the level targeted in women.
Unlike women, men have FDA-approved testosterone products, but they are labelled for documented hypogonadism — two low morning levels plus symptoms — not for age-related decline alone.
Strongest for sexual function. Physical function showed a modest gain (20.5% vs 12.6% of men walked 50 m further in six minutes when all trials were combined); mood improved slightly; energy and vitality were not proven.
Because testosterone thickens the blood, guidelines and the trials themselves call for hematocrit, blood pressure and prostate screening before starting and at set intervals afterward.
The trade-offs the research is honest about
Fractures
Despite improving bone density, treated men in TRAVERSE had more clinical fractures than placebo: 3.50% vs 2.46% over a median 3.19 years. That finding is unresolved and is one reason monitoring matters.Snyder PJ et al. New England Journal of Medicine, 2024;390:203–211
Mood
Of 5,204 men in TRAVERSE, 2,643 had significant depressive symptoms. Testosterone produced modest but statistically significant gains in mood and energy — real, but nowhere near an antidepressant.Bhasin S et al. J Clin Endocrinol Metab, 2024;109(7):1814–1826
Blood thickness and clots
Erythrocytosis (a high hematocrit) and pulmonary embolism were reported more often on testosterone than on placebo in TRAVERSE. This is why hematocrit is measured before treatment and re-checked during it.Lincoff AM et al. New England Journal of Medicine, 2023;389:107–117
Fertility
Testosterone suppresses the signal from the brain to the testes, so it lowers sperm production. Men who may want children should raise this before starting — there are alternatives that protect fertility.
What we still don't know
Beyond three years
TRAVERSE followed men for an average of 33 months. Decades of use are supported by experience and observational data, not by a long randomized trial.
Without a diagnosis
Every trial above enrolled men with two fasting levels below 300 ng/dL plus symptoms. Men treated for "wellness" at higher levels sit outside that evidence — and outside the safety data.
The Elevate approach
We test twice before we prescribe: two fasting morning testosterone levels plus a full metabolic panel, then dosing that holds you in the mid-normal range — not above it. Hematocrit, blood pressure, lipids and prostate screening are checked on a schedule, and every plan is reviewed by Dr. Eric W. Anderson, MD with follow-up labs to keep levels where they belong.