What are normal testosterone levels by age? An older photographer mentors a younger one. Testosterone is an important hormone. It helps men develop during puberty, and as they age, it plays a critical ...

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. Testosterone ...

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.

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