Does testosterone therapy really work?


I’ve seen a lot of commercials advertising testosterone therapy for “low T.” Does it live up to its promise? Should I be on it?


I’ve seen the commercials, too. They promise that testosterone therapy for low blood levels of testosterone, or “low T,” will make you feel more alert, energetic, mentally sharp and sexually functional. Testosterone therapy is a good option for some men, but there are also risks.

Testosterone is the major sex hormone in men. Low T can cause low sex drive, low energy, erectile dysfunction and decreased muscle mass. However, other conditions besides low T can also cause each of these symptoms. As men move into their mid-adult years, blood levels of testosterone tend to fall. But this is variable from one man to the next.

In answering your questions, what I want to avoid saying (and you want to avoid reading) is that “it’s complicated.” But sometimes the answer is just plain complicated — because medical science doesn’t have clear answers.

The first question that sounds like it should be simple to answer, but isn’t, is what blood level of testosterone is truly “low.” The first complication is that doctors measure two different types of testosterone: total and free testosterone. It is free testosterone that actually affects things such as sex drive, energy, erectile function and muscle mass.

Some men have normal total testosterone but low free testosterone, and vice versa. To make matters worse, measuring free testosterone blood levels accurately is difficult. Not all laboratories do it well.

When men have very low total and free testosterone, and resulting symptoms, there’s no doubt that testosterone treatments can raise blood levels and improve symptoms. But many men have testosterone levels that are a little bit low, and it’s not so clear that they benefit from treatment.

Testosterone therapy can be delivered through a gel, patch or injection. Most doctors prescribe a gel.

Like most treatments, testosterone therapy carries some potential risks, such as stimulating the growth of prostate cancer and possibly increasing the risk of heart disease.

Here’s what I advise:

  • Consider other causes for your symptoms. Depression, cardiovascular disease and medications can cause erectile dysfunction. Poor sleep could explain low energy. Aging combined with lack of strength exercises leads to reduced muscle mass.
  • Get an accurate assessment. Have both types of testosterone measured between 7 a.m. and 10 a.m., when testosterone is at its daily peak. If either is low, ask your doctor to confirm the result with a second test on a different day.
  • Be mindful of risks if you are considering treatment. With your doctor, consider whether the benefits outweigh the potential risks based on your personal medical history.

Finally, be realistic. Don’t try testosterone therapy in hopes of channeling your more youthful physical or sexual self, of living longer or healthier, or of improving your memory or mental sharpness. Exercising more would be a safer — and more effective — approach for achieving those goals.