Testosterone in [2026]: Separating the Evidence from the Marketing

Testosterone optimization has become a significant health and wellness industry, driven by direct-to-consumer testosterone replacement therapy (TRT) clinics, supplement marketing, and genuine epidemiological data showing declining testosterone levels in men over recent decades. Separating the legitimate clinical concern from the marketing requires looking carefully at what the evidence says.

The Declining Testosterone Evidence

Studies comparing testosterone levels across generations do show declining average testosterone levels — about 1-2% per decade since the 1980s in several cohort studies. The reasons are not definitively established but are associated with increased obesity rates (adipose tissue converts testosterone to estrogen), sedentary lifestyle, sleep disruption, and possibly environmental factors including endocrine-disrupting chemicals. This is a real population-level finding, not a marketing invention, though the degree of individual impact and the appropriate clinical response is more contested than the trend itself.

The clinical threshold for low testosterone (hypogonadism) is typically established at 300-350 ng/dL total testosterone by most clinical guidelines, with symptoms present. The range of "normal" is wide (300-1000 ng/dL), and where you fall in that range matters less than whether you have symptoms attributable to low testosterone. Many men with testosterone in the lower-normal range experience no symptoms; some with levels in the mid-range experience significant symptoms. Symptoms first, numbers second, is the clinical approach.

What TRT Actually Does and Who It's For

TRT for men with genuinely low testosterone and corresponding symptoms produces clear benefits: improved energy, libido, body composition, mood, and bone density in well-designed studies. For men with clinical hypogonadism (testosterone clearly below normal with symptoms), TRT is a legitimate medical treatment with a good evidence base. For men with testosterone in the lower-normal range and non-specific symptoms (fatigue, reduced motivation, difficulty with body composition), the evidence for benefit is weaker — these symptoms have many causes, and treating them with TRT when testosterone isn't clearly deficient is less clearly effective.

The risks of TRT that deserve honest acknowledgment: it suppresses natural testosterone production (requiring ongoing treatment once started and potentially permanently); it reduces sperm production (a significant consideration for men who may want children); it increases red blood cell count (requiring monitoring); and the long-term cardiovascular effects at population scale remain subject to ongoing research. These risks are manageable under appropriate medical supervision but are real and shouldn't be dismissed by clinics primarily motivated by the subscription revenue model.

Lifestyle Factors That Genuinely Affect Testosterone

Before considering TRT, the lifestyle factors with meaningful evidence for testosterone optimization: resistance training (particularly compound movements at adequate intensity) consistently produces testosterone increases and prevents age-related decline; sleep (testosterone is primarily produced during sleep, particularly deep sleep — chronic sleep deprivation substantially reduces testosterone); body composition (reducing excess body fat, particularly visceral fat, improves testosterone levels through the estrogen conversion mechanism); zinc and vitamin D deficiency correction (common deficiencies with testosterone-relevant effects). These interventions produce meaningful effects for men with modifiable risk factors and should precede TRT evaluation.

My honest take: Get tested if you have symptoms. Optimize lifestyle (resistance training, sleep, body composition) before TRT. TRT is appropriate for clinical hypogonadism under medical supervision — not for optimization in men with normal-range testosterone. Avoid subscription clinics that treat everyone who inquires.