Testosterone is a sex hormone that regulates a number of processes in the human body, including fertility, sex drive, bone mass, fat distribution, muscle mass, and red blood cell production.

Testosterone is the main sex hormone in men. It’s best known for its role in the development of male sexual characteristics and physical features, but there are also many surprising and lesser known ...

This article was reviewed by Felix Gussone, MD. If you've been feeling a bit more couch potato than go-getter lately, dragging through the day, snapping at people for no reason, or wondering where ...