Anabolic-androgenic steroids (AAS) are a synthetic form of testosterone, which is the primary male sex hormone
They affect various parts of your body, such as your muscles, hair follicles, bones, liver, kidneys, and reproductive and nervous systems.
Humans naturally produce this hormone.
In men, its levels increase during puberty to promote the development of male sex traits, such as body hair growth, a deeper voice, sex drive, and increased height and muscle mass.
Though traditionally thought of as a male hormone, women also produce testosterone but in much smaller amounts. It serves several functions for women, primarily promoting bone density and a healthy libido
Normal testosterone levels range from 300–1,000 ng/dL for men and 15–70 ng/dL for women. Taking steroids raises levels of this hormone, which causes effects such as increased muscle mass and strength