Testosterone Education Center
Testosterone therapy (TRT): clinical evidence vs. real-world experience
TRT is used for symptomatic, lab-confirmed low testosterone. Clinical trials show modest but meaningful improvements in sexual function and mood for many men, increases in lean mass and strength, correction of some forms of anemia, and gains in bone density (fracture reduction evidence is mixed). Large safety data suggest cardiovascular risk is not increased when therapy is appropriately prescribed and monitored. As with any hormone therapy, individualized dosing and regular labs (hematocrit, lipids, PSA as appropriate) are essential. Note that exogenous testosterone can suppress sperm production—use alternatives if you’re trying to conceive.
Beyond trials, there’s a wide range of real-world reports—some men describe better energy, focus, and libido within weeks, while others need dose/formulation adjustments to feel their best. Responses vary by baseline health, delivery method (gel vs. injections), and adherence.
Want to go deeper? Click the FAQ items and Clinical Studies buttons below to explore the evidence, safety considerations, and practical tips so you can make an informed decision.
What is TRT and who is it for?
Endocrine Society Guideline AUA Guideline
Sexual function and mood: what do RCTs show?
NEJM: TTrials (Sexual/Vitality) NEJM Review (2025)
Lean mass & strength: what to expect?
NEJM Review (2025)
Bone: density vs. fractures
JAMA Intern Med: Bone Density Trial NEJM (2024): Fractures Trial
Anemia: does TRT help low hemoglobin?
JAMA Intern Med: Anemia Trial
Heart safety: where does the evidence land?
NEJM 2023: TRAVERSE CV Safety JAMA 2017: Coronary Plaque Study
Fertility: can I be on TRT if I want kids?
AUA: Fertility Statements Review: Testosterone is a Contraceptive
Monitoring & common risks (Hct, OSA, PSA)
Endocrine Society: Monitoring Review: Erythrocytosis Thresholds Review: TRT & Sleep Apnea
Gels vs injections—does it matter?
Guideline: Formulations
Anecdotes: energy, mood, libido (varies by individual)
Thread: Early Wins Thread: Pros & Cons
Anecdotes: gels vs injections & practical tips
Thread: Gel vs Injection Thread: Methods Compared
Anecdotes: fertility journeys (hCG/SERMs)
Thread: Fertility after TRT Thread: Protocol While on TRT