Too Much Testosterone, or Estrogen, or Both?

Taking steroids has been in the news, at least for athletes. But some seniors are getting testosterone supplements, and women have taken estrogens a lot in the past. So information on a recently recognized risk may be important.

Yale researchers have shown that abnormally high levels of testosterone increase the death rate of neurons, and can therefore have long term effects on brain function. This finding fits, to a degree, with a report in the Annals of Neurology that Alzheimer’s disease in men aged 71 to 91 is associated with high levels of endogenous estrogen. (Endogenous means ‘produced by the body’, rather than taken in from outside; but endogenous estrogen in men is derived from testosterone that they have in their body.) In the past both elevated testosterone and estrogen levels have been linked to Alzheimer’s, says one of the investigators. But the study shows that only estrogen, not testosterone, is associated with the occurrence of dementia.

It seems to me that these results need reconciling. In the meantime (as I’m fond of saying) the answer is to avoid taking hormone supplements, if possible.