Testosterone is an important hormone. It helps men develop during puberty, and as they age, it plays a critical role in helping control fat levels, cholesterol, and glucose levels.

Starting around age 40, many men notice the first physical changes that may be related to their hormone levels: Energy wanes ...

Boys born to mothers who have polycystic ovary syndrome (PCOS) or who have higher levels of testosterone during the third trimester are more likely to be less physically active at age 7, ...

Total testosterone measures the full amount of the hormone in your blood, while free testosterone represents the small, ...