Testosterone: An Honest Clinical Guide to Testing, Lifestyle, Therapy, and Risk

Testosterone may be the most discussed and least understood hormone in medicine right now. Walk through any airport and you will see advertisements for low-T clinics promising vitality in a vial. Scroll social media and you will find influencers attributing every symptom of modern life, fatigue, low libido, difficulty building muscle, to low testosterone, with supplementation positioned as the obvious fix.

The reality is more nuanced, and more interesting, than either the marketing or the backlash against it suggests.

This is the conversation I have repeatedly in my practice: when testing actually makes sense, what you can do before reaching for a prescription, what is quietly lowering your testosterone without your knowledge, when therapy is genuinely warranted, what the real risks are, and how the different forms of treatment actually work.

When to Consider Testing

Testosterone testing should be driven by symptoms, not curiosity alone. The hormone exists on a continuum, and a low number without symptoms is a very different clinical situation than a low number with a constellation of symptoms that meaningfully affects quality of life.

The symptoms that should prompt consideration of testing in men include persistent fatigue that is not explained by sleep or stress, reduced libido or sexual function, difficulty building or maintaining muscle mass despite consistent training, increased body fat particularly around the midsection, depressed mood or reduced motivation, difficulty concentrating, and in more advanced cases, reduced bone density or anemia.

The challenge clinically is that nearly all of these symptoms overlap significantly with sleep deprivation, depression, hypothyroidism, chronic stress, and simply the demands of a high-performance life. This is precisely why testosterone should be evaluated in the context of the whole clinical picture rather than ordered reflexively whenever someone feels tired or notices their workouts are not producing the results they used to.

When testing is appropriate, it should include total testosterone, ideally drawn in the morning when levels are highest and most representative, along with sex hormone binding globulin, or SHBG, and free testosterone, either measured directly or calculated from total testosterone and SHBG. Total testosterone alone can be misleading. A man with high SHBG can have a low total testosterone with normal free testosterone, and the reverse is also true. LH and FSH help distinguish primary testicular causes from pituitary or hypothalamic causes, which matters for both treatment approach and for identifying other conditions that may need separate attention.

Rather than fixating on a single numeric cutoff, the more clinically useful approach is to interpret the testosterone level in the context of the symptoms present, repeat testing to confirm a low result is not an isolated artifact, and rule out reversible contributors before considering this a fixed diagnosis requiring lifelong treatment.

What Lowers Testosterone, Often Without People Realizing It

Before any conversation about testing or treatment, it is worth examining what may already be suppressing testosterone in ways that are entirely within someone's control to address.

Sleep deprivation is among the most significant and underappreciated factors. The majority of daily testosterone release occurs during sleep, concentrated in REM cycles. Men who sleep five hours or less per night show measurably lower testosterone than those sleeping seven to eight hours, and the effect is dose-dependent. For the high-performing executive who treats sleep as optional, this is frequently the single most impactful and most ignored variable.

Chronic stress and elevated cortisol suppress testosterone production through effects on the hypothalamic-pituitary-gonadal axis. Cortisol and testosterone are, in a meaningful sense, biologically competing priorities. Sustained high stress, the kind common in demanding careers, chronic overtraining, or unresolved life stressors, keeps the body oriented toward cortisol-driven survival responses at the expense of androgen production.

Excess body fat, particularly visceral fat, increases aromatase activity, the enzyme that converts testosterone to estrogen. This creates a self-reinforcing cycle: excess fat lowers testosterone, and lower testosterone makes it easier to accumulate more fat, particularly in the visceral compartment.

Alcohol suppresses testosterone production directly and impairs the liver's ability to clear estrogen, compounding the hormonal disruption. Even moderate regular consumption has a measurable suppressive effect.

Chronic overtraining, particularly excessive endurance training without adequate recovery, can suppress testosterone through the same HPA axis stress mechanisms as other chronic stressors. This is a particularly important point for high-performing patients who assume more training is always better.

Certain medications, including opioids, some antidepressants, and chronic glucocorticoid use, can meaningfully lower testosterone and should be considered in any evaluation.

Nutritional deficiencies, particularly in zinc and vitamin D, are associated with lower testosterone, though providing additional supplementation in a person who is not actually deficient does not raise testosterone further.

Raising Testosterone Without Supplementation

For many men with mildly to moderately low testosterone, particularly when an identifiable lifestyle contributor is present, addressing the underlying factors produces meaningful improvement before any prescription is considered.

Resistance training, particularly compound movements with adequate intensity, produces acute and, with consistency, measurable chronic improvements in testosterone. This is one of the clearest reasons that the periodized, progressive strength training I have written about previously matters for hormonal health specifically, not just for muscle mass or cardiovascular fitness.

Sleep optimization is frequently the single highest-leverage intervention available. Improving sleep duration and quality, particularly increasing time in REM and deep sleep, has a direct and often underestimated effect on testosterone production.

Body composition improvement, specifically reducing visceral fat, reduces aromatase activity and removes one of the primary drivers of testosterone-to-estrogen conversion. This connects directly to the visceral fat discussion I have covered separately, since the mechanisms driving visceral fat accumulation and the mechanisms suppressing testosterone overlap significantly.

Stress management, through whatever combination of strategies actually works for a given person, whether that is structured recovery, therapy, meditation, or simply better boundaries around work, reduces the chronic cortisol elevation that suppresses the HPA-gonadal axis.

Alcohol reduction, even short of complete elimination, removes a direct testosterone suppressant and reduces the burden on hepatic estrogen clearance.

Correcting genuine nutritional deficiencies, specifically vitamin D and zinc when actually deficient on testing, can normalize testosterone in men where deficiency was a contributing factor. This is not a reason to supplement empirically without testing.

For many men, addressing these factors seriously for three to six months meaningfully changes the clinical picture, sometimes obviating the need for therapy altogether, and in other cases clarifying that the low testosterone is not primarily lifestyle-driven and genuinely warrants treatment.

When Testosterone Therapy Is Warranted

In men, therapy is generally appropriate when there is a consistently low testosterone level on repeated morning testing, a clear and bothersome symptom picture that aligns with the lab findings, and reversible contributors have been addressed without adequate resolution. The diagnosis of hypogonadism is a combination of biochemical and clinical findings, not a number in isolation.

It is worth being direct about a complicating reality: a meaningful number of men seeking testosterone therapy today do not have classic hypogonadism. They have suboptimal but not frankly low testosterone, significant symptom burden from overlapping causes, and an understandable desire to feel and perform better. This is a legitimate conversation to have, but it is a different conversation than treating a clearly hypogonadal man, and it deserves to be approached with that distinction made explicit rather than blurred.

In women, testosterone therapy is more specific and limited, but still important to keep in mind. The primary evidence-based indication is hypoactive sexual desire disorder in postmenopausal women, where multiple randomized trials and a 2019 global consensus statement support modest benefit. Testosterone is not currently FDA-approved for this indication in the United States, meaning use is off-label, typically with compounded preparations or careful off-label use of male formulations at substantially reduced doses.

Outside of sexual function, the evidence for testosterone therapy in women for energy, mood, cognition, or body composition is considerably weaker and more inconsistent than the evidence for HRT with estrogen and progesterone that I have written about separately. This does not mean it never has a role, but the expectations should be calibrated to what the evidence actually supports, rather than to the broader cultural narrative about testosterone as a universal vitality hormone.

Side Effects, Risks, and Monitoring

This is the section that deserves the most clinical seriousness, because testosterone therapy is not a benign intervention, and patients deserve to understand what they are actually signing up for.

Erythrocytosis, an increase in red blood cell mass reflected by rising hematocrit, is among the most common and clinically significant effects of testosterone therapy. Elevated hematocrit increases blood viscosity and is associated with increased risk of venous thromboembolism and, at higher levels, stroke. This is the single most important lab value to monitor regularly, and persistently elevated hematocrit may require dose reduction, a switch in formulation, therapeutic phlebotomy, or discontinuation.

Prostate considerations remain a nuanced area. The historical concern that testosterone therapy causes prostate cancer has been substantially revised by more recent evidence, which has not shown a clear causal link in men without preexisting prostate cancer. However, testosterone can stimulate growth in existing prostate cancer, and PSA along with digital rectal exam where appropriate should be monitored, with particular caution and shared decision-making in men with risk factors or a prior prostate cancer history.

Cardiovascular risk has been an area of genuine scientific evolution. Earlier observational data raised concern about increased cardiovascular events, while more recent and more rigorous trials, including the 2023 TRAVERSE trial, a large randomized cardiovascular safety trial in men with hypogonadism and either existing cardiovascular disease or high risk, found no increased risk of major adverse cardiovascular events with testosterone therapy compared to placebo. This is genuinely reassuring data, though it does not eliminate the need for individualized risk assessment, particularly given the erythrocytosis effect discussed above, which is itself a cardiovascular risk consideration independent of the direct cardiovascular safety data.

Lipid effects are generally modest, though testosterone therapy can lower HDL cholesterol to a small degree, which is worth tracking in the context of an overall cardiovascular risk assessment, not in isolation.

Fertility is suppressed by exogenous testosterone, which shuts down the body's own LH and FSH production and reduces sperm production, sometimes substantially. This is an important conversation for any man who wishes to preserve fertility, and alternative approaches exist for that specific situation that are beyond the scope of this discussion.

Other effects include potential acne, fluid retention, breast tenderness or gynecomastia from peripheral aromatization to estrogen, and in women, the possibility of voice changes, increased facial or body hair, and clitoral enlargement, particularly at supraphysiologic doses, which underscores the importance of conservative dosing in women specifically.

A reasonable monitoring framework includes testosterone levels and hematocrit at baseline and at regular intervals during the first year of therapy, PSA in men where age-appropriate, a lipid panel, and ongoing clinical assessment of symptom response relative to the goals that prompted treatment in the first place.

Forms of Testosterone Therapy

Intramuscular or subcutaneous injections of testosterone cypionate or enanthate remain among the most common and cost-effective options. Weekly or twice-weekly dosing, in the range of 50 to 100 mg per injection depending on the regimen and individual response, tends to produce more stable levels than older once-every-two-week protocols, which often produced a noticeable peak and trough effect that patients experienced as a rollercoaster of energy and mood. Subcutaneous injection, using a much smaller needle than traditional intramuscular dosing, has become increasingly popular due to comparable efficacy with less discomfort.

Topical gels and creams, such as branded products applied daily to the shoulders, upper arms, or abdomen, offer a needle-free option with steadier daily levels than older injection protocols, though absorption can be variable between individuals and there is a real risk of transference to others through skin contact, requiring careful attention to application sites and covering treated skin until fully absorbed.

Subcutaneous pellets, inserted under the skin typically every three to six months, offer the convenience of infrequent dosing without daily application or weekly injections. The tradeoff is that the dose cannot be adjusted once implanted, so any issues with too high or too low a level must be managed until the pellet's effect wanes, and minor procedural risks exist with insertion.

Nasal gel formulations exist as a less commonly used option, applied multiple times daily, with the advantage of avoiding transference risk but the disadvantage of a more demanding dosing schedule.

Oral formulations, including newer options that avoid the liver toxicity concerns of older oral testosterone preparations, have become more available, offering a needle-free and gel-free alternative, though long-term comparative data remains more limited than for injectable and topical options.

The right formulation depends on an individual's priorities around convenience, tolerance for injections, lifestyle considerations such as skin-to-skin contact with partners or children, and how their body responds to the pharmacokinetics of each option. There is no single best choice. There is only the best choice for a specific person's physiology and life.

The Bottom Line

Testosterone therapy is neither the universal vitality solution that aggressive marketing suggests, nor the dangerous intervention that older, now substantially revised data once implied. It is a legitimate medical treatment for a specific clinical picture, with real benefits, real risks, and a monitoring framework that deserves to be taken seriously by both physician and patient.

Before reaching for a prescription, the lifestyle factors that influence testosterone, sleep, training, body composition, stress, and alcohol, deserve genuine attention, both because they may resolve the issue and because they remain relevant even for patients who do go on to start therapy.

For those who do need treatment, the goal is not simply restoring a number to a normal range. It is addressing genuine symptoms, with appropriate monitoring, in a way that is honest about both what testosterone can do and what it cannot.

References

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2. Lincoff AM, Bhasin S, Flevaris P, et al. Cardiovascular Safety of Testosterone-Replacement Therapy. New England Journal of Medicine. 2023;389(2):107-117.

3. Davis SR, Baber R, Panay N, et al. Global Consensus Position Statement on the Use of Testosterone Therapy for Women. Journal of Clinical Endocrinology and Metabolism. 2019;104(10):4660-4666.

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6. Cohen J, Nassau DE, Patel P, Ramasamy R. Low Testosterone in Adolescents and Young Adults. Frontiers in Endocrinology. 2019;10:916.

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9. Corona G, Rastrelli G, Di Pasquale G, Sforza A, Mannucci E, Maggi M. Testosterone and Cardiovascular Risk: Meta-Analysis of Interventional Studies. Journal of Sexual Medicine. 2018;15(6):820-838.

Dr. Schraga is a concierge physician and Certified Strength and Conditioning Specialist at Crescendo MD in Portola Valley, California, specializing in preventive and longevity medicine for executives and families in Silicon Valley.