Testosterone replacement therapy (TRT) is surrounded by strong opinions and persistent misconceptions, some of which overstate its risks and some of which overstate its benefits. This article corrects five common misconceptions using current evidence. Correcting a misconception is not the same as recommending treatment: TRT is a prescription therapy for diagnosed low testosterone, it is not appropriate for everyone, and some people should not use it at all (see the contraindications below).
What TRT is
TRT raises testosterone in men with an abnormally low level (hypogonadism), confirmed by blood testing. Testosterone regulates facial and body hair, sperm production, libido, bone density, red blood cell production, and muscle mass. When levels fall abnormally low and cause symptoms, a physician may consider treatment to return them to the normal range. The aim is to relieve symptoms of a diagnosed deficiency, not to enhance normal physiology.
Misconception 1: TRT always increases the risk of heart problems
What the evidence shows: A large 2023 randomized trial found that in men with low testosterone who already had or were at high risk for cardiovascular disease, testosterone gel was not associated with an increased risk of major cardiac events such as heart attack or stroke [1].
Two important qualifiers. First, this trial studied men who already had both low testosterone and cardiovascular risk; it is not evidence about healthy men or about enhancement use. Second, cardiovascular safety remains an area of ongoing study and medical debate. Anyone considering TRT should be assessed and monitored by a physician such as an endocrinologist or urologist.
Misconception 2: TRT causes prostate cancer
What the evidence shows: The concern traces to a single 1941 case report suggesting testosterone could stimulate existing prostate cancer cells. Larger, more recent studies have not reproduced that effect in men without pre-existing disease; a 2023 randomized trial of men with hypogonadism and low PSA found no increased prostate cancer incidence compared with placebo over 14 months [2].
Prostate monitoring remains part of appropriate care. Diagnosis, screening, and treatment decisions are made with a physician.
Misconception 3: TRT turns men aggressive or “hyper-masculine”
What the evidence shows: Testosterone’s relationship with aggression is complex and context-dependent [3], and a meta-analysis of studies manipulating testosterone found no reliable causal link to increased aggression at physiological or therapeutic doses [4]. TRT restores testosterone toward a normal range in men who are deficient; it does not create a personality. Much of this misconception comes from dramatized media portrayals.
Misconception 4: TRT causes hair loss
What the evidence shows: Male-pattern hair loss is driven largely by genetics. Testosterone can contribute to hair loss in men who are genetically predisposed, but TRT is not established as a cause of hair loss in men who were not already prone to it. (One often-cited study reporting hair regrowth involved androgen-deficient women treated with testosterone implants, a different population and delivery method, so it is not direct evidence about men [5].) The reasonable summary is that testosterone does not universally or inherently cause hair loss, and for men who need TRT for a diagnosed deficiency, hair effects are one of several factors to discuss with a physician.
Misconception 5: TRT reverses aging
What the evidence shows: TRT is not an anti-aging treatment. In men with a diagnosed deficiency due to age, injury, or illness, it can relieve specific symptoms and support energy, libido, muscle mass, and bone density. It does not reverse aging, and taking testosterone when the body already produces normal amounts increases risks, including blood thickening and clot risk, testicular shrinkage, reduced sperm production, and acne.
Who should not use TRT
Some people should not use TRT. This includes anyone with:
- Breast cancer or prostate cancer
- Prostate nodules or induration, or an elevated PSA pending evaluation
- Elevated hematocrit or a clotting disorder (thrombophilia)
- Untreated severe sleep apnea
- Congestive heart failure, or a recent history of stroke or heart attack
This is not a complete list. Eligibility is determined by a physician.
The bottom line
TRT is a legitimate, prescription-only treatment for diagnosed low testosterone, and both its risks and its benefits are frequently misstated in either direction. It is not appropriate for everyone, and it is not a shortcut to youth or performance. Decisions should be made with a clinician who specializes in hormone health, based on your testing and medical history.
When to speak with a provider
If you have symptoms that concern you, speak with a licensed healthcare provider about whether hormone testing is appropriate for you.
Disclaimer
This article is for general information only and, like all content on Gambit’s Health Hub, is not a substitute for professional medical advice, diagnosis, or treatment. For any health concern, consult a licensed physician.
References
- Lincoff AM, Bhasin S, Flevaris P, et al. Cardiovascular safety of testosterone-replacement therapy. New England Journal of Medicine. 2023;389(2):107–117. doi:10.1056/NEJMoa2215025.
- Bhasin S, Travison TG, Pencina KM, et al. Prostate safety events during testosterone replacement therapy in men with hypogonadism: a randomized clinical trial. JAMA Network Open. 2023;6(12):e2348692. doi:10.1001/jamanetworkopen.2023.48692.
- O’Connor DB, Archer J, Wu FCW. Effects of testosterone on mood, aggression, and sexual behavior in young men: a double-blind, placebo-controlled, cross-over study. Journal of Clinical Endocrinology & Metabolism. 2004;89(6):2837–2845.
- Geniole SN, Bird BM, McVittie JS, Purcell RB, Archer J, Carré JM. Is testosterone linked to human aggression? A meta-analytic examination of the relationship between baseline, dynamic, and manipulated testosterone on human aggression. Hormones and Behavior. 2020;123:104644. doi:10.1016/j.yhbeh.2019.104644.
- Glaser RL, Dimitrakakis C, Messenger AG. Improvement in scalp hair growth in androgen-deficient women treated with testosterone: a questionnaire study. British Journal of Dermatology. 2012;166(2):274–278. PMID: 21967243.
