Optimal longevity in men is associated with dihydrotestosterone (DHT) levels between 9.8-15.8 nmol/L.

“Now, dihydrotestosterone is important in the body. It reduces fat. It's good for the heart, good for the mind. It has some other downsides. It actually helps your prostate grow as you get older and you need to go to the bathroom. So the real question is, what are the best levels for optimal longevity? And actually there was a study on that. There was a study of 3,690 men that found that the levels of that hormone were optimal if they were relatively low, but within middle range of 9.8 to 15.8 nanomoles per liter. And those were the men that lived the longest.”