Men whose testosterone sits in the lowest fifth of the range were more likely to die of cancer over the following years, a pooled analysis of 11 long-running studies has found. The data covered more than 26,000 men of varying ages, each followed for at least five years.
The finding does not mean low testosterone causes cancer. Think of it more like a check-engine light: it doesn’t say what is wrong, but it says to look. The researchers also stress that it is no reason for men to start taking testosterone supplements.
The work was published in The Lancet Healthy Longevity.
Where the risk starts
Testosterone was measured in nanomoles per liter. Young, healthy men usually fall between 10 and 30 nmol/L. Cancer deaths began to rise once levels dropped below 8.6 nmol/L. For a cancer diagnosis, the risk grew below 7.3 nmol/L.
“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,” said endocrinologist Bu Yeap of The University of Western Australia.
Yeap said the team set out to learn whether blood hormone levels were tied to a man’s chances of being diagnosed with cancer or dying from it. Testosterone has close links to cell growth, and its connection to cancer risk had not been clear.
The prostate exception
One cancer broke the pattern: prostate cancer. That surprised the authors, since the prostate responds strongly to testosterone signals. Lowering testosterone is a treatment for the disease, so doctors have long asked whether a man’s own hormone level affects his risk.
“But based on our findings, there’s no evidence they are related,” Yeap said.
The data did show that lower levels of sex hormone-binding globulin and luteinizing hormone went with a higher chance of a prostate cancer diagnosis. Why the prostate behaves differently needs more study.
What men should do
Yeap sees testosterone as a biomarker. Checking it, he suggested, could help identify men who might do poorly if they get cancer down the track.
His advice for men found to be low is to see a doctor for a full check-up. “It may not show any sign of testicular disease, but it might show other health issues or risk factors they need to address,” he said.
He added that the result could be “a wake-up call and encouragement for men to engage in more healthy lifestyle behaviors, and to get regular, holistic checkups.”
Sources
- Low Testosterone Is Linked to a Higher Risk of Cancer, Study Finds
- Low Testosterone Is Linked to a Higher Risk of Cancer, Study Finds
