By the age of 60, majority of individuals will only have 25% of the Growth Hormone they once had at age 20. Furthermore, about 50% of 80 year olds have no detectable growth hormone. There have been numerous studies using GH therapy in the ageing population showing improvements in areas such as: lean muscle mass, total body fat, bone and cardiovascular regions. Additionally, restoring youthful levels of GH have also been shown to improve sleep, cognitive functions and mood to name a few.
IGF1 (insulin-like growth factor 1) and IGF-BP3 (insulin-like growth factor binding protein 3)
Insulin- like growth factor (IGF1) is a natural hormone occurring in your body which produces a necessary protein determined by the IGF1 gene. It includes seventy amino acid polypeptides that are produced by the liver and endocrine hormone. IGF-1 also plays an important role in childhood growth, but also has anabolic effects in adults such as cellular repair to muscles, brain, and heart.
Insulin- like growth factor (IGF-1), also known as somatomedin C, is a hormone similar in molecular structure to insulin. IGF-1 production is stimulated by growth hormone (GH) and debilitated due to poor or under nutrition, growth hormone insensitivity, and lack of growth hormone receptors. Approximately 98% of IGF-1 is always bound to one of 6 binding proteins (IGF-BP). IGFBP-3, the most abundant protein, accounts for 80% of all IGF binding. IGF-1 binds to IGFBP-3 in a 1:1 molar ratio.
IGF-1 is a primary mediator of the effects of growth hormone (GH). Growth hormone is made in the anterior pituitary gland, released into the blood stream and then stimulates the liver to produce IGF-1. IGF-1 then stimulates systemic body growth and has growth-promoting effects on almost every cell in the body especially skeletal muscle, cartilage, bone, liver, kidney, nerves, skin and lungs. In addition to the insulin-like effects, IGF-1 can also regulate cell growth and development especially in nerve cells as well as cellular DNA synthesis.