Growth hormone (GH) or somatotropin, also known as human growth hormones (hGH or HGH) in its human form, is a peptide hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals. It is thus important in human development. GH also stimulates production of IGF-1 and increases the concentration of glucose and free fatty acids. It is a type of mitogen which is specific only to the receptors on certain types of cells. GH is a 191-amino acid, single-chain polypeptide that is synthesized, stored and secreted by somatotropic cells within the lateral wings of the anterior pituitary gland.
In its role as an anabolic agent, HGH has been used by competitors in sports since at least 1982, and has been banned by the IOC and NCAA. Traditional urine analysis does not detect doping with HGH, so the ban was not enforced until the early 2000s, when blood tests that could distinguish between natural and artificial HGH were starting to be developed. Blood tests conducted by WADA at the 2004 Olympic Games in Athens, Greece targeted primarily HGH. Use of the drug for performance enhancement is not currently approved by the FDA.
The major isoform of the human growth hormone is a protein of 191 amino acids and a molecular weight of 22,124 daltons. The structure includes four helices necessary for functional interaction with the GH receptor. It appears that, in structure, GH is evolutionarily homologous to prolactin and chorionic somatomammotropin. Despite marked structural similarities between growth hormone from different species, only human and Old World monkey growth hormones have significant effects on the human growth hormone receptor.
Effects of growth hormone on the tissues of the body can generally be described as anabolic (building up). Like most other protein hormones, GH acts by interacting with a specific receptor on the surface of cells.
1 Faster weight loss
Higher human growth hormone levels give you more energy, which means you’ll burn more calories during your workouts and while doing daily activities. And that means you’ll burn fat and lose weight faster.
2 Faster recovery from workouts
Human growth hormone cuts down the time it takes you to recover – between both exercises and workouts. If you’re doing a circuit-type workout, for example, you’ll be able to recover faster between exercises when your HGH levels are elevated.
3 Strength gains
The amount of strength you produce is highly dependant on the amount of HGH you have flowing through your body. It’s true that bigger muscles can move bigger weights, but having the strength to move the weights in the first place is paramount.
4 Muscle growth
The increased energy HGH gives you also helps you build more muscle. It takes energy to push heavy weights around. Plus, the previous strength gains benefit goes hand in hand with this one. Extra strength will lead to more muscle and vice versa.
5 Hair growth
Higher human growth hormone levels result in better physical characteristics in the body – such as healthier hair and faster hair growth.
6 Better brain function
HGH contributes to the brain as much as the body. When your human growth hormone levels are high, so is your ability to think and focus.
7 Higher sex drive
Your sexual function is directly related to your testosterone and human growth hormone output. When they are on an even keel, so is your sexual appetite. HGH can even help you achieve better erections.
8 Elevated mood
You can’t always be in a good mood. But if your HGH levels are lower than normal, you’ll have an even tougher time being happy. However, when your levels are on par, the game changes. Your mood will stay elevated and you’re less likely to be anxious.
9 Better sleep
It’s during sleep that your body goes into recovery mode – both physically and mentally. If you deprive yourself of sleep, this will have an adverse effect on your wellbeing, and your human growth hormone release.
On the flipside, if your HGH levels are normal or high, you’ll have no trouble falling asleep or staying asleep, which means you’ll feel more refreshed the next day.
10 Stronger Bones
You need strong bones to support your body when you’re doing anything physical. Elevated HGH levels keep your bones stronger and more resistant to breaks – especially important as you begin to age.
Injection-site reaction is common. More rarely, patients can experience joint swelling, joint pain, carpal tunnel syndrome, and an increased risk of diabetes. In some cases, the patient can produce an immune response against GH. GH may also be a risk factor for Hodgkin’s lymphoma.
One survey of adults that had been treated with replacement cadaver GH (which has not been used anywhere in the world since 1985) during childhood showed a mildly increased incidence of colon cancer and prostate cancer, but linkage with the GH treatment was not established.