Millions of American men now get regular doses of testosterone, enticed by the promise that they’ll feel more energetic, alert, confident, mentally sharp, and sexually functional. And many of them do experience these benefits.
But as always, there’s a lot more to the story, including controversy over potential complications and cancer risks…
What is testosterone replacement therapy?
Testosterone is critical to a man’s health. It helps maintain bone density and fat distribution, regulates muscle strength and mass, and prompts the production of facial and body hair, as well as sperm production and red blood cell production. And of course, it affects sex drive.
Testosterone levels peak around late adolescence and early adulthood for men. But after age 30, a man’s testosterone levels drop roughly one percent per year, which is one reason why a 55-year-old man can’t expect to have the same energy level as a 25-year-old man.
Still, some doctors have convinced many men to see testosterone replacement therapy (TRT) as a solution to the body’s natural loss of testosterone and the changes that it brings. Over the last several years, sales of prescription testosterone injections, gels and patches have grown significantly; so have reports of side effects.
Some men using these low-dose testosterone products report experiencing acne, breast and ankle swelling, interrupted sleep, increased aggression, and hair loss.
“Because of the marketing, men have been flooded with information about the potential benefit of fixing low testosterone, but not with the potential costs,” says Dr. Carl Pallais, an endocrinologist and assistant professor of medicine at Harvard Medical School. “Men should be much more mindful of the possible long-term complications.”
Just what are the long-term risks?
Cardiovascular problems are at the top of the list, but the evidence is conflicting. Some research shows that men who use testosterone therapy over the long term are at higher risk for heart attacks, strokes, and complications from heart disease.
In 2010, researchers halted the Testosterone in Older Men study when early results showed that men on testosterone replacement therapy experienced a dramatically higher number of heart problems.
Researchers believe that part of the reason for this is because TRT may prompt your body to make too many red blood cells, and a high red blood cell count increases clotting risk.
However, other studies have disputed these findings. In a review published in 2012 in the Indian Journal of Urology, researchers wrote, “Androgen (testosterone) administration seems to be beneficial in decreasing fatal cardiovascular events, body fat mass, and insulin resistance.”
Does TRT cause prostate cancer?
There’s also the lingering concern from some physicians that TRT could trigger prostate cancer by elevating PSA levels and stimulating the growth of prostate cancer cells.
This belief began in the 1940s when two medical researchers discovered that when a man’s testosterone production dropped, his prostate cancer stopped growing.
In addition, these researchers, Charles Brenton Huggins and Clarence Hodges, found that when they gave testosterone to men who had prostate cancer, their cancers grew.
Since then, conventional medicine has used hormone therapy to treat certain prostate cancers by lowering testosterone in a man’s body.
However, in recent years, numerous studies have found no link between high levels of testosterone and prostate cancer. In fact, just the opposite. Some studies have found a higher risk of prostate cancer among men with the lowest testosterone levels.
In 2016, a meta-analysis of twenty research reports published in the British Journal of Urology found no relationship between testosterone levels and prostate cancer.
Another review, which included men who already had prostate cancer, found that testosterone therapy didn’t increase prostate cancer risk or make the cancer more severe for existing prostate cancer sufferers.
And researchers investigating testosterone replacement therapy’s effects on prostate specific antigen (PSA) levels—a protein that can signal prostate cancer—found no increase in PSA in men undergoing TRT. These researchers published their findings in the journal Medicine.
Over the years, I’ve talked with numerous doctors and reviewed quite a lot of research on TRT and prostate cancer. I believe testosterone supplementation does not cause prostate cancer.
However, because prostate cancer is so common, doctors generally tend to steer clear of prescribing testosterone supplementation to men who have had prostate cancer or may be at high risk for the disease.
Evaluating your need for testosterone therapy
“General fatigue and malaise is pretty far down my list (for starting TRT),” says Dr. Michael O’Leary, a urologist at Harvard-affiliated Brigham and Women’s Hospital. “Tons of men who would never have asked me about it before started to do so when they saw ads that say, ‘Do you feel tired?’ But if they have significant symptoms, they’ll need to have a lab test. In most men the testosterone level is normal.”
Testosterone levels should only be measured between 7am and 10am, when they’re at their highest. You should be tested by your own family doctor, and not at a clinic where TRT therapy is sold. Any low reading should be confirmed with a second test on a different day, ideally with an endocrinologist.
In the meantime, consider that there are several other things you can do to boost your testosterone levels naturally, safely and cheaply. Getting at least 30 minutes of cardio activity daily will help improve your natural testosterone levels – and will also contribute to better sleep. Eating a balanced, nutritious diet is also known to naturally boost testosterone.
If you do opt for TRT therapy, loop your physician in on a regular basis to get testosterone checks outside of the lab where you’re getting supplementation, and also to make sure your prostate and blood chemistry aren’t showing any signs of complication.
“There is a bit of a testosterone trap,” Dr. Pallais says. “Men get started on testosterone replacement and they feel better, but then it’s hard to come off of it. On treatment, the body stops making testosterone. Men can often feel a big difference when they stop therapy because their body’s testosterone production has not yet recovered.”
- “Are testosterone-boosting supplements effective? Not likely.” University of Southern California – Health Sciences, 26 June 2019.
- “Testosterone replacement and prostate cancer.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3424887/
- “Effect of testosterone boosters on body functions: Case report.” By AmerAbdulrahmanAlmaiman, Int J Health Sci (Qassim). 2018 Mar-Apr; 12(2): 86–90. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5870326/
- “Endogenous and exogenous testosterone and the risk of prostate cancer and increased prostate-specific antigen (PSA) level: a meta-analysis”
- “The effect of testosterone replacement therapy on prostate-specific antigen (PSA) levels in men being treated for hypogonadism: a systematic review and meta-analysis”
- “Is testosterone therapy safe? Take a breath before you take the plunge.” From Harvard Men’s Health Watch, 14 December 2018.https://www.health.harvard.edu/mens-health/is-testosterone-therapy-safe-take-a-breath-before-you-take-the-plunge
- “Supplemental testosterone: Healthy or not?”From Piedmont Healthcare.
- “Testosterone therapy: Potential benefits and risks as you age.” By Mayo clinic Staff for Mayo Clinic, 4 April 2020.https://www.mayoclinic.org/healthy-lifestyle/sexual-health/in-depth/testosterone-therapy/art-20045728