Testosterone is the principal male sex hormone, or androgen, produced mainly by the testes.

As the primary male hormone, or androgen, testosterone regulates various aspects of your growth and development as a man. Testosterone plays a central role in shaping both your physical ...

Testosterone's effects on the body are wide ranging, including helping you grow and repair muscle and bone, produce red blood cells and stabilize mood and libido. During male puberty, testosterone ...

Though testosterone often gets a bad rap because aggressive or misbehaving men are sometimes labeled as "testosterone fueled," the hormone actually isn't unique to one type of person or gender and ...

Testosterone plays a central role in shaping both your physical characteristics and reproductive functions, like your growth, sperm production, muscle mass, and deeper voice. It also influences your ...