Human growth hormone, also known as HGH, is an essential hormone secreted by the anterior pituitary gland. Human growth hormone functions to promote development and growth in our younger years. As we age, growth hormone has an essential role in keeping our muscles and minds healthy and can directly affect the ratio of bad to good cholesterol levels or stating it scientifically the ratio of high density to low-density lipoproteins in our cholesterol levels and bone density.

Growth hormone secretion levels peak during puberty and start to decline by the age of 30. Most of us can expect a 30-50% decline in our growth hormone production by the time we are in our 50s. Higher than normal declines can lead to several symptoms that left unchecked can be the cause of any number of life-threatening diseases. There can be many causes for growth hormone deficiencies in adults. When an adult has low or absent secretion of growth hormone from the pituitary gland, they will have growth hormone deficiency. This can be an inherited or acquired condition. Inherited growth hormone deficiency may be associated with an abnormal pituitary gland.

Acquired growth hormone deficiency is usually caused by damage to the pituitary gland or the hypothalamus, a part of the brain that controls the pituitary gland. This may be due to a tumor; to surgery or radiation used to treat the tumor; head injuries or to problems with the blood supply to the pituitary gland. The vast majority of adult cases of hormone deficiency relate to aging. As we age the systems of the body slow down, the pituitary gland or the master gland that makes growth hormone also slows down. Adults approaching 30 start to see the effect of aging as it relates to the pituitary gland. Some adults for no apparent reason see more drastic reductions in their levels than others.