Growth Hormone (GH) is the master hormone, because it is released by the master gland - the anterior pituitary gland. While GH is not necessary or critical to one's survival, it seems to play an important evolutionary role in human development. During puberty, GH levels dictate a person's height and bone size. After puberty, GH continues to regulate the body's metabolism. Growth Hormone supplements are not HGH (human growth hormone), they are products designed to increase your body's natural production of GH from the pituitary gland.