12% of men on testosterone meet guidelines, University of Michigan study finds

Testosterone therapy is supposed to be precise medicine, not a vibe. But in a University of Michigan study of 200 men prescribed testosterone at a university clinic, only 12% met the criteria for treating low testosterone, confirmed by two blood tests. That means 88% may have been receiving testosterone without meeting the study’s guideline-based threshold.

And that gap is not just academic. The study flags potential downstream harms for men who did not appear to truly qualify for treatment, including infertility concerns, cardiovascular events like heart attack and stroke, and long-term dependence on TRT that can dampen the body’s natural testosterone production. The researchers also note that some of those men may have had conditions like sleep apnea or prostate cancer, which matters because testosterone can worsen certain risks.

So what does it mean to “meet the criteria”? The source frames testosterone replacement therapy (TRT) as something that should start with confirmation, not assumptions. Healthy testosterone levels are crucial for energy, sex drive, muscle, and metabolism, but the clinical pathway is not “symptoms equal TRT.” A blood test should check for low testosterone, and it is typically taken first thing in the morning and then confirmed with a follow-up blood test on a different day. In this framework, low testosterone is anything below 300 nanograms per deciliter for most healthy adult men. Clinicians also need to rule out related conditions that can drive low testosterone readings, such as sleep apnea, which the source notes can worsen with testosterone therapy.

This is where the popularity of testosterone becomes a double-edged sword. The article describes testosterone-maxxing and fitness and longevity trends, and it connects the cultural moment to broader demand drivers. It notes that TRT use has quadrupled in the past three decades, up to as many as 11 million Americans. Interest in the hormone is also described as widespread in 2026, spanning social media “T-maxxing” trends and the US government’s MAHA campaign. When demand grows faster than clinical guardrails, the risk is that testosterone shifts from measured endocrinology to fast, sometimes sloppy prescribing.

The University of Michigan findings sharpen the concern with specifics about who received prescriptions. The men studied were on average in their 50s, but the article says some were as young as 18. That age detail is important because the study’s concern extends beyond immediate side effects. If young men who do not truly need TRT take testosterone, the source warns that it could put long-term health at risk by making it harder for the body to produce its own supply of the hormone over time. High testosterone levels can also increase the volume of red blood cells, which is described as a risk factor for high blood pressure and, in extreme cases, may lead to a heart attack or stroke.

Fertility is the other big second-order problem. The article states that testosterone can temporarily reduce sperm count, which can impair fertility. And it adds that taking testosterone can potentially exacerbate serious health conditions like prostate cancer, potentially fueling tumor growth, pointing to the Mayo Clinic for that risk framing. Put together, these are not minor side effects. They are the kinds of outcomes that can turn a wellness trend into a safety and liability headache for clinics, payers, and anyone building patient programs around TRT.

Still, the story is not a simple “TRT bad” headline for providers. The source includes a counterweight from Dr. Justin Dubin, director of men’s sexual health at Baptist Health Medical Group, who was not involved in the study. Dubin’s key point is that prescribing TRT outside guidelines may not always be harmful, and that guidelines are “guidelines, they’re not law.” He emphasizes the existence of “gray areas,” arguing that most doctors and most patients live there. He also says testosterone’s growing popularity can be a gateway to men’s health, because it can pull people into clinical care where they can learn about blood pressure, diabetes, or heart disease. In his view, the upside is especially meaningful when men speak to a doctor rather than just buying stuff online.

That gray-area theme is also reflected in the regulatory and professional landscape. The source says the American Urological Association has gathered a panel to discuss a major update to its guidelines on treating testosterone deficiency in the coming year or two. In other words: even while the University of Michigan study calls out guideline non-meeting as a safety risk, the field is actively working on what the “right” standard should be. For decision-makers, that creates both uncertainty and urgency. Uncertainty, because standards may evolve; urgency, because current practice appears to be drifting away from whatever “safe and effective treatment” currently means on paper, at least in the study setting.

The strategic stakes are broad. If TRT is being prescribed to a majority of men who do not meet guideline criteria confirmed by two blood tests, then men’s health organizations face a quality-of-care problem, not just a messaging problem. And for executives, investors, or operators watching men’s health programs, it raises the question of execution: are clinical workflows built to verify eligibility, check for confounders like sleep apnea, and monitor response appropriately? The answer will shape outcomes, reimbursement risk, and reputational risk. The field is moving fast, but the hormone is unforgiving when safety checks get skipped.