Your Sexual Prime Is Not About Testosterone

8 min readThe first time Mark slept with a new partner after ending his 20-year marriage, he was so in his head he couldn’t stay hard. Embarrassed by his inability to perform, the 47-year-old turned to TikTok and Instagram for advice on erectile dysfunction and aging. Soon enough, his feed was inundated with looksmaxxers, biohackers, and government goons all touting testosterone as the magic bullet for optimal manhood, including sexual performance.You’ve probably seen the posts and, like Mark, are curious about whether testosterone replacement therapy (or TRT) lives up to the hype. Prescriptions for testosterone have increased 154 percent since 2020, mainly among men in their late 30s and 40s. This surge stems from the proliferation of both the manosphere on social media and TRT telehealth clinics in the U.S. The increase in marketing and access has convinced men that testosterone is both the cause and cure of all their problems.It is true that men’s testosterone naturally declines about 1 percent every year after age 30, but there is evidence that a large proportion of healthy men have low testosterone without any issues. In fact, research shows that content creators tend to promote the fallacy that “low-T” is a men’s health crisis, and TRT clinics often prescribe hormones to men with borderline healthy levels sans adequate monitoring.And because TRT signals to the brain to stop making testosterone naturally, patients have to keep coming back for more treatments once they start. Contrary to what TRT clinics want you to think, more is not necessarily better. Heightened levels of testosterone can actually get converted into estrogen and lead to erectile dysfunction.Eventually, after getting less-than-satisfactory answers from social media, Mark asked his doctor about hormone testing. “Based on my bloodwork, she didn’t think there was any need.”So, What Actually Influences Sexual Desire as You Age? Young men tend to display more obvious sexual behavior, have fewer health problems, and experience more spontaneous erections. “This produces a simple story: Testosterone is highest in young adulthood; therefore, sexual desire must also be highest then,” says Toivo Aavik, PhD, an associate professor of psychology at the University of Tartu who studies sexual behavior and men’s health. “But low sexual desire is not evidence of low testosterone.”Despite these stereotypes about youth and libidos, men’s sexual desire actually peaks around age 40 and remains relatively stable until the age of 60, according to a 2026 study conducted by Aavik and his team. The researchers found that, throughout midlife, libido depends more on variables like relationship satisfaction, past masturbation frequency, and physical health factors, such as stress and sleep, than testosterone alone. So, even if your testosterone starts to naturally dip after your thirtieth birthday, you’ll likely still be 40, horny, and thriving.This tracks for Mark. Once he got past his initial nerves, the novelty of dating new people has had a greater impact on his libido than his potentially declining testosterone levels. “My desire has remained the same throughout my forties and probably increased due to my circumstances,” he says.It is worth noting that Aavik and his research team did not track individual men’s testosterone over time, and instead looked at what men, ages 20 to 84, had to say about their levels of sexual desire. Then, they cross-referenced this with what is already known about age-related testosterone decline. As a result, Aavik cannot say that sexual desire increases at 40, but rather, the libido you have in your 20s and 30s remains relatively stable until your 60s.Oh, and FYI: You don’t have to have a “high” libido to have a “healthy” sex life. “Some people simply have less sexual desire than others, and this is not necessarily a medical problem,” says Aavik.How Do I Know if My Libido Is Healthy?Men have a reputation for avoiding the doctor, but “the penis is what brings guys into the office,” says San Francisco-based urologist Judson Brandeis, MD, meaning concerns about erectile dysfunction and fertility.You may be convinced that your issues are testosterone-related, but asking your doc to test your T levels can also provide a jumping-off point to discuss other aspects of your health, like your heart. Low testosterone and erectile dysfunction often get conflated, but ED can be an early sign of cardiovascular problems, while low testosterone may be due to a lack of self-care. To be fair, ED and low T can occur simultaneously, so it makes sense why you might be concerned about both.Plenty of men, from different backgrounds and with varying health factors, worry about decreasing sexual desire as they age. When those guys show up in Dr. Brandeis’ office, here’s what he recommends:Improve your sleep.Sleep is one of the most significant lifestyle factors impacting testosterone levels in men under 60 because the brain produces luteinizing hormone when you’re catching Z's, which signals the testes to produce testosterone. When your sleep suffers, your testosterone can temporarily decline until rest is resolved. Of course, other health habits like nutrition, exercise, medication, and drug and alcohol consumption can also impact both sexual desire and testosterone levels—by either helping or hindering sleep hygiene.But if following the classic sleep hygiene advice (limit screen time before bed, sleep in a cool, dark room, etc.) isn’t cutting it, a more serious health concern, like sleep apnea and insomnia, may be the cause. There is a strong correlation between both conditions and low testosterone, as well as ED. If you have sleep apnea, your doctor may recommend snoozing with a CPAP (continuous positive airway pressure) machine. Doing so improved erectile function in people with severe obstructive sleep apnea, per a 2019 study in Sleep Medicine. Oral appliances that reposition the jaw or tongue during sleep can also help some folks with mild to moderate sleep apnea.If insomnia is the issue, you should speak with a sleep specialist, according to Wendell Bobb, MD, assistant professor of neurology and sleep medicine at George Washington University School of Medicine. “There is often a precipitating event such as stress, sleep-wake schedule changes, medications, or depression that initially causes the insomnia,” he previously told Men’s Health. “But the insomnia can persist long after that inciting event. Therefore, the earlier the sleep disturbance is diagnosed and treated, the better.” Whatever you do, try not to lose sleep over concerns about either diagnosis.Monitor erection frequency. Some guys experience erectile dysfunction due to biological reasons, such as a side effect of medications like antidepressants. Others have ED due to psychological reasons, like anxiety about having sex for the first time after a divorce. One clear way to tell the difference between mental and physical ED is whether you still experience spontaneous erections, typically in the morning or at night. You might not care if the issue is mental or physical when you’re struggling to get it up in the moment, but distinguishing the difference is key for your doc to determine the correct course of treatment.For instance, if you’re having erections overnight or first thing in the morning, but cannot get them with a partner, odds are your issue is psychological. In those situations, ED medications like Viagra can be a viable interim solution. But if you’re not waking up with morning wood on a regular basis (or at all), the cause is likely biological and may require lifestyle changes in addition to medication. Point is, admitting you have a problem—by tracking your arousal or lack thereof—is the first step to figuring out a solution.Get a blood test. Whether it's low libido, performance issues, or something else, sexual health is inextricably tied to overall health, and a comprehensive blood panel is necessary to determine what is really going on. Bloodwork will flag any underlying prostate, kidney, liver, and cardiovascular issues, along with potential deficiencies in B12, vitamin D, or iron.Btw, where you get your bloodwork done matters. It’s best to work with a trusted physician, but the increasing availability of TRT via telehealth clinics has led some men to pursue “self-managed testosterone and bloodwork.” Meaning, they are conducting their own lab work with direct-to-consumer blood tests and primarily relying on information from the internet and crowdsourced on social media, which can lead to dangerous oversights.Bottom line: Experimenting with your hormones based on self-managed bloodwork can impair your ability to produce testosterone and make it harder for physicians like Dr. Brandeis to reverse that damage.When Testosterone Is to Blame Testosterone may be overemphasized as a catch-all cure for the ailments of age, but that doesn’t mean some men don’t genuinely struggle with low T. It’s just that other factors, like sleep and occupation, can tank your testosterone more than simply getting older.Dr. Brandeis tends to see hormonal imbalances in night-shift workers because the majority of testosterone production happens during sleep. He also occasionally encounters men in their 40s with lower testosterone who have highly physical jobs, like construction and ironwork, which can deplete it. When that happens, it is easy to address through clinical interventions, Dr. Brandeis says, including but not limited to TRT.Before a man starts TRT, however, it's important to know if he wants to have children. Hormones taken therapeutically tell the brain to stop making them naturally, which can inhibit sperm production and lead to infertility. That is why urologists like Dr. Brandeis tend to prescribe clomiphene, also known as Clomid, first. Its intended use is to stimulate ovulation in women, but it can be prescribed off-label to spur natural testosterone production in men, without risking infertility the way TRT does. If this does not move the needle enough, doctors can prescribe testosterone in conjunction with clomid, in order to preserve natural hormone and sperm production.Speaking of kids, men also tend to go through a temporary testosterone decline after becoming dads, which scientists suspect is a biological response meant to shift their focus from mating to caregiving. This is a normal postpartum period for men that can be exacerbated by a lack of sleep, poor diet, lack of exercise, and other negative lifestyle changes that come with early parenthood. Fortunately, hormones usually rebound as children become more self-sufficient, which is why TRT isn't typically recommended in these instances.In the rare instances when TRT is the suggested course of action, it still isn't a set-it-and-forget-it solution. You need to be monitored every six months to make sure you’re not producing prostate-specific antigen, a protein produced by the prostate gland indicating cancer risk, which can be accelerated by TRT. Doctors also need to make sure you’re not producing too many red blood cells, a side effect of TRT that increases the risk of blood clots, strokes, and heart attacks.Given these risks, it is crucial to talk to a trustworthy doctor about your hormones if you start to notice a dip in sexual desire. You may find that the only testosterone problem you have is in the T-obsessed media you’re consuming.Lauren Vinopal is a writer based in Chicago whose work has been published in GQ, Slate, Mel Magazine, and more.