It is a 191-amino acid, single chain polypeptide hormone that is synthesized, secreted by the somatotroph cells within the lateral wings of the anterior pituitary gland. That's the definition by Wikipedia.
Here is a definition in a layman's terms.
HGH is a hormone that the pituitary glands in our brain creates. It is also known as the youth hormone, because it is responsible for the height increases, calcium retention, increases in muscle mass and the stimulation of the immune system among many others. The problem is, after a certain age HGH secretion starts slowing down.
Around 1990, a study was conducted where HGH was tested on some people over 60. The result showed increase in body mass and bone density. Since then this study has been interpreted as an idication that HGH is an anti-aging agent. Since then HGH has been marketted as a fountain of youth all over the world.
Today HGH is used to treat/cure many ailments. FDA approved a genetically engineered recombinant hormone (aka Serostim) as a therapy for HIV wasting. Serostim increases LBM (lean body mass) and improves physical endurance in HIV patients. HGH is also administered to children with severe growth deficiencies. These are all medical needs.
With demand, HGH started being used by atheletes for performance enhancement and by the rich as an anti-aging therapy. Rich...because these injections are pretty expensive. Obviously, sports authorities started banning the use of Human Growth Hormones. Then as always with the huge business potential, the underground dealing of HGH started. With stories of sportsmen using HGH in the news, the whole misconception of HGH being illegal started. The use and distribution of prescription HGH IS illegal (jail time). The use and distribution of prescription HGH under proper approvals is NOT illegal.
With more demand came companies that started manufacturing non-prescription HGH enhancers or releasers. They came in as sprays and pills. HGH is now being used by millions of people worldwide to control the aging process, to lower fat production, to increase calcium retention and every other benifit that HGH brings to a human body. There are a ton of manufacturers. Some distributers are known to slap two different stickers on the same product and market them as two competing brands of HGH.
There are HGH products that are popular because of their prices and then there are ones that are popular because the company throws more money into advertising them. The consumers determine their favorite and it's not only based on the price, or customer service, or how well established the company is or the side effects of the HGH product etc. Ultimately, how effective the HGH product is will play an important role in how
popular it becomes.
Here is a list of the best HGH.