Considering Testosterone Therapy? This Is What Research Shows

Advertisements for testosterone replacement therapy, or TRT, often promise to help people “regain vitality,” “boost energy,” or “feel young again.” They may mention symptoms with a wide range of causes, and suggest that testosterone replacement therapy could be the solution you’re looking for.

But while TRT can benefit some people with clinically low testosterone, the science is more nuanced than many advertisements suggest. We spoke with Thomas Travison, PhD, senior scientist and director of the Biostatistics and Data Science team at the Hinda and Arthur Marcus Institute for Aging Research, whose research has focused on testosterone and its relationship to aging and health outcomes in older men.

He believes that advertising around TRT often creates unrealistic expectations. “I personally feel the marketing and promise made around is is in excess of what the actual outcome is likely to be for the typical person,” Dr. Travison says.

So, what does research tell us about TRT for older adults? Here’s what you should know. 

Understanding testosterone as we age

Testosterone is a hormone that plays an important role in many functions throughout the body, including maintaining muscle mass and bone strength, regulating body composition, supporting mood, and contributing to sexual function and libido.  

Healthy testosterone levels vary widely from person to person, and there is no single number that defines what “healthy” is for everyone. That said, testosterone levels do begin to drop as we grow older.

Because testosterone levels decline with age, the terms “male menopause” and “andropause” have emerged. These terms are misleading. Unlike menopause in women, which involves relatively rapid hormonal changes, testosterone levels in men decrease gradually over time.  

What is low testosterone? 

While a decline in testosterone over time is normal, some older men do develop clinically low testosterone, known as hypogonadism. A diagnosis of hypogonadism is based on consistently low testosterone levels confirmed through testing and the presence of symptoms associated with testosterone deficiency.

Health care providers often consider testosterone levels low when total testosterone is below 300 nanograms per deciliter, and free testosterone is below 5 ng/dL. That said, testosterone levels vary based on many factors, and you shouldn’t try to interpret lab results on your own.

Symptoms of hypogonadism that may contribute to a diagnosis when accompanied by consistently low testosterone levels include:   

• Low libido 
• Erectile dysfunction
• Osteoporosis or fracture
• Disruptions in sleep
• Low mood or energy
• Decreased physical performance

Remember that many of these symptoms are broad and can have a number of causes other than low testosterone. 

The science behind low testosterone is complex 

Healthy testosterone levels fall across a broad range. For most people, moving from the lower end of that range to the higher end is unlikely to produce noticeable changes in how they feel or function. “Once you’re in a healthy range, TRT is unlikely to radically change how you feel,” explains Dr. Travison.

Additionally, health and lifestyle factors may influence testosterone levels as much as aging itself. Weight, physical activity, and overall health can also influence testosterone levels, which is why physicians consider a person’s broader health rather than focusing solely on testosterone levels.

In some cases, lower testosterone may be the result of underlying health issues rather than the cause of them. That can make it difficult to determine exactly how low testosterone impacts overall health. While low testosterone has been linked to conditions such as frailty, it’s unclear whether it contributes to these conditions or is simply a reflection of a person’s overall health. 

Low-T ads often simplify the science

Ultimately, testosterone is only one piece of the overall health puzzle. Advertisements often suggest that low testosterone is a simple explanation for a variety of symptoms and age-related changes.

“Many of the symptoms attributed to low testosterone are really nonspecific,” Dr. Travison says. “Fatigue, feeling down, sexual disinterest, decreased strength — a lot of these things happen with getting older, lifestyle, or health conditions.”

If a reason other than testosterone is driving your symptoms, TRT is unlikely to resolve them. Addressing other health conditions or lifestyle factors may be more pressing than raising testosterone levels for many people.

That isn’t always clear in advertising. The result is that some people expect greater benefits from TRT than they are likely to experience. 

Who is a good candidate for testosterone therapy? 

None of this means that testosterone replacement therapy is “good” or “bad.” It just means there are big claims about who is a good candidate for TRT. The question isn’t whether TRT works, but who will actually benefit from it.

TRT does have legitimate medical uses for people with hypogonadism. Dr. Travison’s research has shown that testosterone replacement therapy can improve sexual function and other symptoms associated with testosterone deficiency. Given that sexual symptoms are the primary reason older men seek TRT, this finding could be meaningful for those making individualized care decisions.

The Endocrine Society’s Clinical Practice Guidelines recommend diagnosing hypogonadism in men with symptoms consistent with testosterone deficiency and consistently low testosterone levels confirmed through testing. They also recommend against routinely prescribing testosterone replacement therapy to men over 65 with low testosterone levels, instead emphasizing individual evaluation and risk assessment.

While TRT can be an appropriate treatment, it isn’t a one-size-fits-all solution. “There are legitimate, very necessary uses of treatments,” Dr. Travison adds. “But they’re often marketed as lifestyle drugs, and it’s not in the best interest of anyone to be taking medication they don’t need.”

If you’re experiencing symptoms and questioning whether low testosterone could be playing a role, remember that many of those symptoms can have other causes. Before pursuing treatment on your own, talk with your doctor to see if testosterone therapy is a good fit.

Improving lives through aging research at the Marcus Institute 

At Hebrew SeniorLife’s Hinda and Arthur Marcus Institute for Aging Research, researchers study the factors that influence health and aging, from hormones and physical function to cognition and nutrition. 

We also offer opportunities to participate in clinical research studies and trials. Research participants help advance our understanding of aging, contributing to discoveries that can improve the lives of older adults now and in the future.

Learn more about our current clinical trials at the Marcus Institute.