Testosterone Therapy: Help, Hype, or Harm? What the Latest data Really Says

Testosterone therapy is everywhere: online ads, anti-aging clinics, gym locker room conversations. It promises renewed energy, better sex, stronger muscles, and a younger you. But does the science support the hype?

A major review in The New England Journal of Medicine (NEJM) cuts through the noise. Its conclusion is nuanced and important: testosterone therapy can help the right patient, but only with careful diagnosis, selection, and monitoring. For everyone else, the risks may outweigh the benefits.

First, Who Should Actually Get Testosterone?

Testosterone therapy is not for vague symptoms like tiredness, weight gain, or “low motivation” alone.

According to NEJM and professional society guidelines, treatment should be reserved for men with unequivocal hypogonadism, defined as:

• Two separate early-morning, fasting testosterone levels below normal

• Greatest likelihood of benefit when levels are <200 ng/dL

• Clear symptoms such as:

  
  

  • Low libido or reduced sexual activity

  • Loss of body hair

  • Hot flashes

  • Gynecomastia

  
  

Men with testosterone only slightly below normal, especially those with obesity or metabolic disease, are much less likely to benefit.

What Are the Real Benefits?

When testosterone is truly low, treatment can help, but the gains are specific and modest.

Where it helps most

• Sexual health: Consistent improvement in libido and sexual activity

• Anemia: Can correct low hemoglobin

• Mood & function: Small improvements in mood, energy, and walking ability

Key point: Testosterone improves libido more reliably than it improves erectile dysfunction.

Additional benefits seen in studies

• Increased lean muscle mass

• Reduced fat mass

• Improved bone mineral density, especially relevant for older men at risk of osteoporosis or sarcopenia

The Risks You Shouldn’t Ignore

Testosterone is a hormone, not a supplement, and it comes with real risks.

Most notable concerns

• Pulmonary embolism (blood clots in the lungs)

• Higher fracture risk

• Increased atrial fibrillation and non-fatal arrhythmias

The reassuring news?

Large trials, including the TRAVERSE trial, show no increase in major adverse cardiovascular events (heart attack or stroke), even in high-risk men.

The sobering news?

Rates of:

• Atrial fibrillation

• Arrhythmias requiring intervention

• Acute kidney injury

  
  

  were slightly higher with testosterone than placebo.

Absolute risks remain small, but they are real.

What Testosterone Does Not Seem to Increase

Despite long-standing fears, current evidence shows no clear increase in:

• Prostate cancer

• Major cardiovascular events

• Worsening urinary symptoms

That said, high-risk men were often excluded from trials, so caution still applies.

Who Should Not Receive Testosterone?

Guidelines are clear. Testosterone is contraindicated in men with:

• Prostate or breast cancer

• Elevated PSA without urologic evaluation

• High hematocrit (>50%)

• Untreated severe sleep apnea

• Severe urinary symptoms

• Recent heart attack or stroke (within 6 months)

• Uncontrolled heart failure

• Known thrombophilia

• Men planning fertility (testosterone can cause infertility)

Men with a prior blood clot deserve special consideration and may need preventive anticoagulation if therapy is pursued.

Monitoring Is Not Optional

Testosterone therapy requires structured follow-up, not “set it and forget it.”

Monitoring should occur at:

• Baseline

• 3-6 months

• Annually

And include:

• Symptom response

• Testosterone levels (target: mid-normal range)

• Hematocrit

• PSA (men ≥40)

• Urinary symptoms

• Blood pressure and adverse effects

If sexual function doesn’t improve within 12 months, guidelines recommend stopping therapy.

Cost, Convenience, and Formulation

• Intramuscular injections are often far cheaper than gels or patches

• Effectiveness and safety are similar

• Choice should reflect patient preference, lifestyle, and risk profile

There is no “best” formulation, only the best fit for the individual.

The Bigger Preventiononly Takeaway

Testosterone therapy is not an anti-aging shortcut.

It is:

• Helpful for carefully selected men

• Ineffective for many with nonspecific symptoms

• Associated with small but meaningful risks

• Dependent on data-driven diagnosis and close monitoring

At Preventiononly, we believe true longevity comes from understanding your biology, addressing root causes, and avoiding unnecessary medicalization.

Before chasing a hormone, ask:

Is my testosterone truly low, or is something else driving how I feel?

Because prevention starts with asking the right questions: not just filling a prescription.

References

(NEJM, Endocrine Society, ACP, TRAVERSE trial, and peer-reviewed sources as listed above)

1. Testosterone Treatment in Middle-Aged and Older Men with Hypogonadism. Bhasin S, Snyder PJ. The New England Journal of Medicine. 2025;393(6):581-591. doi:10.1056/NEJMra2404637.

2. Testosterone Therapy: Review of Clinical Applications. Petering RC, Brooks NA. American Family Physician. 2017;96(7):441-449.

3. Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. Bhasin S, Brito JP, Cunningham GR, et al. The Journal of Clinical Endocrinology and Metabolism. 2018;103(5):1715-1744. doi:10.1210/jc.2018-00229.

4. Testosterone Replacement Therapy for Male Hypogonadism. Heidelbaugh JJ, Belakovskiy A. American Family Physician. 2024;109(6):543-549.

5. Male Hypogonadism. Basaria S. Lancet (London, England). 2014;383(9924):1250-63. doi:10.1016/S0140-6736(13)61126-5.

6. The Role of Testosterone in the Elderly: What Do We Know?. Barone B, Napolitano L, Abate M, et al. International Journal of Molecular Sciences. 2022;23(7):3535. doi:10.3390/ijms23073535.

7. Anabolic-Androgenic Steroid Use in Sports, Health, and Society. Bhasin S, Hatfield DL, Hoffman JR, et al. Medicine and Science in Sports and Exercise. 2021;53(8):1778-1794. doi:10.1249/MSS.0000000000002670.

8. Male Hypogonadism: Pathogenesis, Diagnosis, and Management. De Silva NL, Papanikolaou N, Grossmann M, et al. The Lancet. Diabetes & Endocrinology. 2024;12(10):761-774. doi:10.1016/S2213-8587(24)00199-2.

9. Association of Testosterone Therapy With Risk of Venous Thromboembolism Among Men With and Without Hypogonadism. Walker RF, Zakai NA, MacLehose RF, et al. JAMA Internal Medicine. 2020;180(2):190-197. doi:10.1001/jamainternmed.2019.5135.

10. Efficacy and Safety of Testosterone Treatment in Men: An Evidence Report for a Clinical Practice Guideline by the American College of Physicians. Diem SJ, Greer NL, MacDonald R, et al. Annals of Internal Medicine. 2020;172(2):105-118. doi:10.7326/M19-0830.

11. Testosterone Treatment in Adult Men With Age-Related Low Testosterone: A Clinical Guideline From the American College of Physicians. Qaseem A, Horwitch CA, Vijan S, et al. Annals of Internal Medicine. 2020;172(2):126-133. doi:10.7326/M19-0882.