Test Details: GH, also known as human growth hormone, is a substance that controls your body's growth. It also helps control metabolism, the process of how your body uses food and energy. GH is made in the pituitary gland, a small organ in the base of the brain. In children, GH plays a major role in bone growth, development of muscle mass, and height. In adults, GH affects bone and muscle health. GH tests are used to diagnose GH disorders, including gigantism, and to evaluate pituitary function.