Last week, a research letter published in the Journal of the American Medical Association—using data from a sample of nearly five hundred military members—reported that approximately twenty-five per cent of participants had at least one measured testosterone level that could qualify them as deficient. The letter is something of a Rorschach test, offering new information that could either bolster or undermine Pete Hegseth’s effort to establish a “high-T Department of War.” Universal screening for testosterone deficiency among men thirty and older has become one of Hegseth’s signature policies: “No fatties, no trannies, no beardos, no weirdos,” he crankily told a crowd of mid-level military members last month, during his “State of the Force” speech. “The patriotic cowboys are in—with testosterone testing on top.”
Every relevant medical society recommends against screening asymptomatic men for testosterone deficiency, because it is akin to scouring a hotel room with a black light: you’re going to find a lot of stuff of indeterminate significance that you wish you hadn’t seen. The data in the JAMA letter, collected across five U.S. military sites between August, 2024, and January, 2026, suggests that more than a hundred thousand men in current service could qualify for testosterone-replacement therapy (TRT) if their screening results are treated as diagnostic. Other military data collected between 2018 and 2025 had estimated the prevalence of diagnosed testosterone deficiency in male military members at less than one per cent.
This variation reflects that a diagnosis of testosterone deficiency can be made rigorously, with a desire to rule out, or capaciously, with a desire to rule in. Decreased testosterone is often cited as an explanation for an array of nonspecific symptoms, including depressed mood, poor libido, fatigue, and spotty memory. Serum testosterone levels vary with stress, sleep, body shape, and time of day; borderline low levels are common and are hard to interpret outside the context of a careful clinical evaluation. Different organizations even use different thresholds to determine what a “low” value is: the Centers for Disease Control uses two hundred and sixty-four nanograms per decilitre, whereas the American Urological Association and the military use three hundred.
These ambiguities make the condition a perfect container for all manner of dysphoria and shame, and set patients and doctors up for conflict. Before prescribing TRT, evidence-based doctors will require multiple confirmatory tests, disregard symptoms that are vague and easily attributed to other causes, and recommend other interventions to boost testosterone production. Patients who are intent on starting injections may then flee to wellness influencers and direct-to-consumer prescribers. “I’ve been experiencing lack of energy, motivation, and 0 sex drive,” an aspiring T user lamented on Reddit’s r/Testosterone forum, dismayed that his physician would not offer him a prescription because his blood work looked fine.
TRT might restore a man’s sex drive, build lean muscle, and boost energy, but it can also accelerate hair loss and lead to abnormal blood counts and clotting. (It also carries a risk of infertility; wanton TRT use among America’s soldiers risks doubling as an inadvertent sterilization effort.) Nonetheless, testosterone prescriptions have accelerated wildly in recent years, both from licensed sources and on the gray market. The fastest growth has been among young people, who sometimes inject doses intended to push testosterone levels far beyond the usual physiologic range.
In the MAHA/MAGA manosphere, the epithet “Low T” stands in for a failure to meet increasingly punitive standards of maleness. “It’s about restoring and optimizing your natural capabilities, protecting your longevity, and insuring you have the biological foundation required to sustain the fight,” Hegseth said when he announced the policy in July, emphasizing that America’s soldiers should remain on “the leading edge of lethality.” But optimization is a goal with no clear threshold for success: one can always look better, feel better, or, I suppose, be something closer to a killing machine. Hegseth is promoting gender-affirming care for cis men, encouraging them to better align their bodies with his idea of what they should be.
When I learned about testosterone deficiency during medical school, twenty years ago, the term referred to a circumscribed diagnosis requiring the presence of specific signs and symptoms: absent libido, infrequent erections, scant body hair, and blood work demonstrating low morning testosterone levels on multiple occasions. It was considered uncommon, especially in young men, yet under-recognized in many instances. (The most common genetic cause of primary testosterone deficiency is the presence of an extra X chromosome; it’s a disorder called Klinefelter syndrome, which goes undiagnosed in upward of fifty per cent of cases.) I’ve never diagnosed low T, although I’ve had patients request an evaluation. This means I’ve probably missed it, but not in the patients who thought they had it.
Separately, doctors have long prescribed TRT to older men for quality-of-life reasons. Men’s testosterone production decreases with age, and older men might experience its lack in much the same way that menopausal women experience decreased estrogen production: fatigue, loss of libido, increased frailty. In both of these cases, hormone prescriptions are not recreational, but they are elective; the drug is being used to supplement rather than restore, and “the real question is benefit” rather than diagnosis, Brad Anawalt, an endocrinologist and men’s-health expert at University of Washington School of Medicine, told me.
Over the past decade, however, several factors have shifted the norms around who seeks a testosterone prescription and who gets one. “Hormones have become magical,” Anawalt said, and testosterone is “the most magical of all. It’s genuinely hard to have a candid conversation about the science of testosterone with almost anybody, because there’s so much emotion in it.” In part, this is because low testosterone, which was previously treated as a source of individual suffering, has been cast as a social crisis. Testosterone levels have dropped worldwide by as much as fifty per cent since the nineteen-seventies—a decrease associated with the rising prevalence of obesity, because excess fat tissue decreases the production of testosterone and its binding proteins.
Low T due to obesity is best treated through weight loss and life-style modifications, but because testosterone supplementation can help shed pounds, many men would rather start there. Members of online testosterone forums often introduce themselves by sharing their age, their weight, and, sometimes, a photo. After a period on testosterone, they’ll post an “after” shot—washboard abs, straining traps, bulging pecs. “You look superb, man” is a typical encouraging response; “kind words, bro, thank you” a customarily humble reply.
In addition to obesity, some researchers posit that hormone-disrupting chemicals, such as the phthalates and bisphenol A (BPA) found in certain plastics, may have a role. This is a favorite preoccupation of Robert F. Kennedy, Jr., and who himself has copped to taking testosterone supplements to maintain his ropey physique, and who calls the global testosterone drop an “existential problem.”
A worldwide decrease in testosterone is notable, and might be a problem, but its public-health significance isn’t yet clear. Testosterone has been measured differently over time and across studies, often without controlling for relevant concerns such as participant B.M.I. or presence of symptoms. Kennedy told a Fox News host that “a teen-ager today, an American teen-ager, has less testosterone than a sixty-eight-year-old man,” which is a dramatic overread of current trends: with the data we have, we can say with confidence only that average testosterone levels have decreased over time, but not much about in whom, why, or what it means. Lower testosterone on average across a cohort doesn’t equate to meaningful clinical deficiency in an individual, since a fifty-per-cent drop might still land someone comfortably within the normal range. Still, some researchers—and many men seeking testosterone prescriptions—argue that “normal” should be an age-adjusted variable. “To optimize your overall physical (sexual/athletic/aesthetic) performance, a man 40s and 50s needs to be in the 700-1000 range,” one r/Testosterone regular advised his comrades.
Low testosterone is often diagnosed without any measured testosterone recorded for the patient at all. Data from 2018 suggests as many as one quarter of men are prescribed testosterone without recent blood work. That’s what we know from the doctor-to-pharmacy world; we have much less insight into the prescribing habits of direct-to-consumer (D.T.C.) platforms, and even less clarity on how much testosterone is being purchased on the gray market with no prescription at all. In one study, D.T.C. providers were happy to prescribe testosterone to a secret shopper with a level of 675 ng/dl. Whatever we might think the rate of testosterone use is, it’s almost certainly an undercount.
The Trump Administration draws a sharp distinction in legitimacy between the use of hormone therapy in the case of transgender-affirming care versus in cisgender-affirming care. I asked Anawalt to help me puzzle over why I consider these interventions discontinuous with one another, rather than variations on a theme. “The trans population I take care of—a fair number of them aren’t looking to become something different than the gender they feel they are,” Anawalt told me. “They’re not looking to become supermen or superwomen.” This was a provocative suggestion: that transgender care, by offering harmony between a body and an identity, is, in a sense, naturalizing, whereas TRT used to compensate for insecurity and enhance masculinity might be the more unnatural intervention.
Testosterone’s current cultural ubiquity “reduces masculinity to a single number,” Anawalt said, even as that number fluctuates and means little out of context. Hormones work via exquisitely calibrated feedback systems, sensitive to all sorts of stresses and rhythms, acting as messengers across our internal ecologies to keep things in balance—a balance that can easily be disrupted by circumstance. In 2020, a group of researchers led by Christopher Frueh, a clinical psychologist at the University of Hawaii at Hilo, published a description of Operator syndrome, a cluster of symptoms—including sleep disturbances, psychiatric illness, chronic pain, and hormone disruptions, and symptoms of traumatic brain injuries—observed in some special-operations personnel after prolonged periods of physical and emotional stress. Testosterone deficiency is a feature of Operator syndrome, and Hegseth has cited the condition as a rationale for his screening program.
Yet it seems reductionist to think of the individuals who fit this profile as primarily “testosterone deficient.” Rather, testosterone production is suppressed in men living under stressful conditions as “an adaptation to energy scarcity, not a disease, and it typically resolves within days of restored sleep and intake,” as the military’s own document on testosterone screening acknowledges. Evidence that TRT helps men with Operator syndrome is mostly hypothetical, and no prospective study has been conducted. In one small case series comparing a handful of special-operations personnel who were on testosterone with those who weren’t, there were no observed benefits in terms of mood, sleep, or sexual function in the men taking TRT. Instead, men on testosterone reported higher pain scores, and researchers noted anecdotal reports of increased irritability and aggression. Several study participants also apparently expressed a belief that, as special forces, they ought to have testosterone levels well above those of a civilian.
There are approximately seventy thousand troops classified as special ops in the United States military, out of a force that contains some two million people. Nonetheless, in twenty-first-century pop culture, depictions of Navy SEALS and other élite fighters in the diffuse and secretive war on terror have come to stand in for the American military as a whole. Hegseth has advocated for operators accused or convicted of war crimes to be pardoned, and routinely references special ops as the embodiment of the “warrior ethos” he strives for. “When the broader force has strayed from the path, has strayed from sanity, has strayed from standards, you have been keepers of the flame,” he told a room of special-ops members in 2025.
Operators are supposed to look a certain way that is decidedly high-T—“You don’t have to be six-foot-three, two hundred and twenty-five pounds, and be able to bench four hundred pounds, but it helps,” the Montana congressman Ryan Zinke, a former SEAL, told Politico. But the American military as a whole looks much more like the country it serves. In 2022, two-thirds of active-duty American service members were overweight or obese, and twenty-one per cent qualified as obese. Given this context, JAMA’s finding that a similar proportion of men might be found to have borderline low testosterone comes as no surprise.
“I think there’s a decent amount of this which is related to just a kind of feeling of humiliation,” the writer Phil Klay, a former marine, told me. “We’re in the wake of failed wars, right? And in the wake of failed wars, there’s always some asshole who is gonna want to say that the reason that we bailed is because we weren’t hard enough, we weren’t cool enough,” he said. Recurrent failures in the Middle East, of course, are low-T; “no fatties” is a plank in Hegseth’s response to those failures.
To live in a state of high T, conversely, is to project a kind of indestructibility. Kennedy once reported that Mehmet Oz had told him that President Trump has “the highest testosterone levels that he’s ever seen for an individual over seventy years old,” and remarked that the President has “the constitution of a deity.” Recently, a young man named Gabe Poirot was interviewed on Fox News about the eighteen days he spent in a coma, in 2021, during which he claims to have met Jesus. “Talk about testosterone!” he marvelled to Kayleigh McEnany. The Jesus he met wasn’t a “soft or passive Jesus,” Poirot recounted, but a man who was huge, strong, and more rageful than anyone imagines, a “lion angry for me. He’s a mustang on my behalf.” In a 2024 survey, nearly eighty per cent of Republican men reported that they thought America had become “too soft and feminine.” Rising anxiety that the future feels suspiciously female may be precipitating the demand for T prescriptions. But the desire also reflects an increasing faith that medicine can ameliorate more ancient types of dread.
In 2012, Stephen Colbert joked that “low T” was “previously known as getting older.” Indeed, in the past decade, death itself began to seem like the ultimate low-T activity. Lower testosterone levels have been associated with higher age-adjusted mortality in some studies, though no trial has demonstrated that higher testosterone leads to a longer life. Still, the idea has stuck. “People are, like, ‘Well, you’re not a younger man anymore’—well, duh? Like, people just want you to wither away and die,” the podcaster and testosterone evangelist Joe Rogan once said. It’s hard to picture how a guy like Rogan, Hegseth, or Kennedy eventually decides to stop juicing. One imagines them as forever brawny, neck veins popping, even as the mortal coil snakes tighter around their chests. ♦