Low testosterone levels linked to higher rates of cancer in men

Testosterone levels have long been linked to poor health. However, this is one of the first major studies to examine the link between low testosterone and cancer risk.

“We wanted to know whether the concentration of these hormones in the blood was related to the risk of men being diagnosed with, or dying from, cancer in the future,” said Bu B. Yeap, an endocrinologist from The University of Western Australia and one of the main authors of the Androgen In Men Study (AIMS), an international collaboration exploring the links between different sex hormones, including testosterone, and cancer in men.

The AIMS research, published last month in The Lancet Healthy Longevity, analyzed long-term data from more than 26,000 men across 11 cohort studies in Europe, Australia, and the United States.

The prior cohort studies analyzed sex hormones in blood samples taken earlier in the lives of men. The AIMS research then matched these samples to cancer outcomes for the same men in the decades following these blood tests.

Hormones analyzed included not just testosterone, but also dihydrotestosterone, one of the major hormones that indicate hair loss, sex hormone-binding globulin (SHBG), and luteinizing hormone, higher levels of the latter two of which were associated with an increased risk of being diagnosed with prostate cancer later in life.

“We wanted to know whether the concentration of these hormones in the blood was related to the risk of men being diagnosed with, or dying from, cancer into the future,” said Yeap.

What Yeap, his team, and their international collaborators learned is that men who had the lowest testosterone levels had a higher risk of dying from cancer, even after taking into account age and other health-related factors.

Having testosterone levels that are 14 percent or more below the normal range is when cancer risk started increasing.

The study authors were careful to note that this link does not necessarily suggest that low testosterone itself helps in the development of cancer. The study strongly suggests that low testosterone can serve as a marker of overall and future health.

“What we would say to men is if they are found for whatever reason to be low in testosterone, it’s important to go to the doctor for a full check-up,” said Yeap. “It may not show any sign of testicular disease, but it might show other health issues or risk factors they need to address.”

“It could be a wake up call and encouragement for men to engage in more healthy lifestyle behaviors, and to get regular, holistic check-ups to stay on top of their health,” he concluded.

For healthy young men, the normal range is usually between 10 and 30 nanomoles per liter (nmol/L), with normal levels tending to decrease in older men, and these normal levels may also be affected by other factors, including body mass index, physical activity, and other medical conditions.

And while low testosterone was found to increase cancer risk, this is not the case when the researchers considered prostate cancer risk. Yeap and the others suggested that this may be because reducing testosterone levels is a regular part of treatment for prostate cancer.