Know anyone taking testosterone? The happy medium is the place to be. Avoid those extremes, high or low.
Chevy Chase, MD—Older men whose testosterone levels were neither low nor high tended to live longer, according to new research accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology & Metabolism.
Testosterone is a key male sex hormone involved in maintaining sex drive, sperm production and bone health. Physicians have long known that low testosterone levels can signal health problems, but the new study found men may not fare better when levels of the hormone rise too high.
Could be that the low testosterone is a sign that someone else is wrong rather than a cause of early death. Though someone without much sex drive probably finds life less worth living.
The part about dihydrotestosterone (DHT) is interesting because some men take drugs (finasteride and dutasteride) that block the conversion of testosterone to DHT. High DHT causes hair loss and prostate enlargement. Are they increasing their mortality risk?
"Older men who had testosterone in the middle range survived longer than their counterparts who had either low or high levels of the hormone," said the study's lead author, Bu Beng Yeap, MBBS, FRACP, PhD, of the University of Western Australia, based in Fremantle Hospital, Western Australia. "When the body metabolizes testosterone, it produces dihydrotestosterone (DHT), which is tied to a lower risk of dying from ischemic heart disease. Having the right amount of testosterone and higher levels of DHT might indicate these men are in better health overall, or it could help them maintain good health as they grow older."
On the bright side, lowering blood DHT seems to cut the risk of prostate cancer.
Too low is worse than too high.
Men with the lowest testosterone levels had the highest cumulative mortality rate, followed by the men with the highest testosterone levels. Men with circulating testosterone levels in the 9.8 to 15.8 nmol/L range tended to live longer.
If we only knew enough about our genetic genetic risks and accumulated damage we could tune our metabolisms with drugs to cut our greatest medical risks without doing much to boost our other medical risks.
|Share |||Randall Parker, 2013 November 25 09:13 PM|