Eunuchs historically lived longer, suggesting that supplementing with testosterone may not be conducive to a longer lifespan.

“the obvious one you know the first or aam's razor view of that would be well that's something about testosterone right and because that's it's not so much that the men who are castrated are getting estrogen and progesterone if you castrate them they're actually going to have no estradi versus the estrad they would have if they could keep their testosterone — but of course that kind of flies in the face of the testosterone replacement data which say well actually it doesn't seem to impact mortality either way”