Men with very low testosterone levels face an 18 percent higher risk of dying from cancer later in life, according to a new international study. The findings suggest that hormone concentrations in blood samples could serve as an early indicator of future health risks, potentially decades before a cancer diagnosis occurs.
The research comes from the Androgens In Men Study (AIMS), an international collaboration led by Professor Bu Yeap at The University of Western Australia. Published in the journal Lancet Healthy Longevity, the project investigates how various sex hormones relate to cancer risk and other health outcomes in men.
Testosterone Threshold and Cancer Mortality
The analysis examined data from more than 26,000 men participating in 11 long-running studies across Australia, the United States, and Europe. Researchers analyzed hormone concentrations in blood samples collected earlier in the men’s lives and compared those measurements with cancer diagnoses and deaths recorded over the following decades.
The study looked at testosterone, dihydrotestosterone (DHT), sex hormone-binding globulin (SHBG), and luteinizing hormone. Luteinizing hormone is produced by the pituitary gland and signals the testes to produce testosterone.
Professor Yeap noted that when baseline testosterone was below 8.6 nanomoles per liter (nmol/L), subsequent cancer risk started increasing. This threshold is significant because testosterone levels in healthy younger men typically range from 10 to 30 nmol/L, although concentrations generally decrease with age.
“What we saw was that if a man had low testosterone levels – in the lowest one-fifth compared to the highest one-fifth of the range – their subsequent risk of dying from cancer was higher, even after allowing for age and other health-related factors,” Professor Yeap said.
The researchers identified a specific concentration below which cancer risk began to rise. Testosterone levels can be influenced by factors that people may be able to change, including body mass index and physical activity. Certain medical conditions, such as diabetes, can also affect testosterone concentrations.
Prostate Cancer Linked to Different Hormones
Surprisingly, the study found that testosterone levels were not associated with prostate cancer risk. Instead, prostate cancer was more closely linked to low levels of two other hormones: SHBG and luteinizing hormone.
This distinction is medically significant because lowering testosterone is an established treatment for prostate cancer. However, the new analysis found no evidence that a man’s natural testosterone concentration was associated with his risk of developing the disease.
“Since reducing testosterone levels is a treatment for prostate cancer there’s always been a question of whether the amount of testosterone your own body makes relates to your risk of prostate cancer but based on our findings there’s no evidence they are related,” Professor Yeap said.
“We did find, however, that men with low levels of SHBG and luteinizing hormone were at higher risk of prostate cancer.”
These results highlight an important distinction between testosterone and other hormones involved in male reproductive function. Although low testosterone was associated with higher overall cancer risk and mortality, prostate cancer showed a different pattern of hormonal associations.
Medical Implications and Lifestyle Factors
The findings raise the possibility that testosterone measurements could help doctors recognize men who may face greater health risks in the future. However, the results show an association and do not establish that low testosterone itself causes cancer.
Professor Yeap emphasized that the findings should not be interpreted as a recommendation to take testosterone supplements to prevent cancer. “While we’ve shown low levels are associated with increased risk, we haven’t got any evidence yet that actually giving men testosterone will reduce that risk,” he said.
Instead, unexpectedly low testosterone could be a reason to investigate a person’s overall health. A medical evaluation may uncover underlying conditions or risk factors that require attention, even when there is no evidence of a problem affecting the testes.
“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 checkup. It may not show any sign of testicular disease, but it might show other health issues or risk factors they need to address,” Professor Yeap said.
He added that low testosterone could serve as a wake-up call for men to engage in more healthy lifestyle behaviors and to get regular, holistic checkups to stay on top of their health.
Source: ScienceDaily
