What is HGH (Human Growth Hormone)

Human Growth Hormone is made up of 191 amino acids. It is a normally occurring hormone that reaches levels often exceeding 800 mcg during your teenage years and early twenties. After this peak, these levels will generally decrease continuously as we age. I believe the the cause of the physical signs of aging is this decrease in hormone levels, contrary to the idea that these levels fall because of aging.

Can we extend life by continuing to keep hormone levels at a youthful level? Claiming that Human Growth Hormone is the “fountain of youth” is not a fair statement; however, the lack of HGH results in the deterioration of numerous bodily functions resulting in the many of the physical signs of aging.

Human Growth Hormone is produced in the anterior part of the Pituitary. The pituitary is located behind the nose, inside of the brain. It is the command center for numerous hormonally controlled critical functions. When patients are born with poor HGH output, they are referred to as pituitary dwarves. Unfortunately, for these patients, their stature is not the only function affected by this lack of HGH. These patients do not live a normal life, aging more quickly, having a higher incidence of cardiovascular disease, recurrent illnesses, healing problems, and deteriorating bone structure. Other patients develop loss of HGH production after surgery or pituitary irradiation, developing significant changes in body composition, metabolism, lipid abnormalities, increased cardiovascular disease, and bone density abnormalities. Patients develop rapidly diminishing levels of growth hormone associated with aging, and though this may be construed as “normal”, the progressive development of life-shortening conditions including cardiovascular disease, obesity, Metabolic Syndrome, the decline in memory and thought processes, and the deterioration of physical activity should be addressed as they are real health issues.

Human Growth is produced usually around 1:00 to 2:00 in the morning, and having a very short half-life of approximately 12 minutes, disappears within one hour. Its production is associated with something called the Arcadian rhythm, or a sleep rhythm. Do you wonder why you wake up at 1:00 in the morning? Growth hormone is produced then and helps one maintain the critical REM sleep. If it is not adequately produced, REM sleep is not obtained and one sleeps too lightly - awakening very easily. The appropriate timing of replacement of HGH will help the patient reach and maintain the restful quality REM sleep.

Growth Hormone is then metabolized in the liver into IGF-1, or insulin-like growth factor. This is the active form of growth hormone, benefiting sleep, cognition, body composition, heart function, heightened immune system, and improved skin quality, only to mention a few systems positively impacted by Human Growth Hormone. Aging correlates closely with the progressive decrease in IGF-1 production. Growth Hormone deficiency is characterized by progressive weight gain (primarily central), decreased lean body mass, and increased body fat. Studies have identified patients with growth hormone deficiency have at least a 7% increase in body fat, mostly central which results in an increased waist-hip ratio, which has been associated with a higher incidence of cardiovascular disease, and shortened life-span. A classic study performed at the Medical College of Wisconsin, and published in the New England Journal of Medicine by Dr. Daniel Rudman in the 90’s identified the benefit of Human Growth Hormone supplementation in patients who were HGH deficient. Two groups identified as Growth Hormone deficient, and were told not to change their eating pattern or exercise regimen. One group was given salt water, a placebo, and the other group a low dose Human Growth Hormone. The two groups were re-examined after 6 months of therapy, and the group who had received Human Growth Hormone demonstrated a 9% increase in lean body mass, and a 16% decrease in total body fat. Without exercising, or eating properly! Imagine what could happen if proper diet, and exercise were incorporated into that therapy.

Other benefits of Growth Hormone therapy include the impact on memory and cognition. The level of IGF-1 in the brain declines rapidly in the aging brain. This decline results in impairment in memory, the ability to learn, spatial memory, and delayed processing with response. IGF-1 has also been identified as important in neuronal and dendritic repair. The falls in IGF-1 and HGH have also been associated with neurodegenerative changes such as Alzheimer’s, Parkinson’s disease, and multiple sclerosis.

Patients who are Growth Hormone deficient appear to have memory issues and associated problems with concentration. Psychological well-being is also affected resulting in increased depression, loss of self-confidence and lack of motivation. Associated with this, patients with low growth hormone deficiency have higher rates of divorce, depression and higher rates of unemployment.

Numerous studies have identified the benefit of Growth Hormone replacement therapy and profound, impressive changes in body composition, with increased lean body mass, and decreased body fat. The improvement in lean body mass has been associated with increased protein synthesis, increased body mass, and exercise tolerance. The decrease in body fat is most significant as visceral fat, or the fat that is within your belly, and is very highly associated with cardiovascular disease. The loss of body fat truncally is most impressive, and often does not affect fat loss in the arms and legs. Then, the classic picture of a Growth Hormone deficient patient, especially males, is one with the large belly and the thin arms and legs. This pattern is probably genetic, but then the associated drop in HGH is also undoubtedly genetic!

There have been numerous studies that identify the cardiovascular benefits of Human Growth Hormone. A meta-analysis was performed in 2004, this approach uses a way of looking at numerous studies all together and determining benefit of the growth hormone, not on one individual study, but on the results of numerous well designed studies that were randomized to patient selection, blinded to the researchers on what the patients were receiving, and compared to placebo or basically receiving an injection of salt water instead of growth hormone. This approach is the absolute best way to determine the benefit of a therapy, and the best statistically. Dr. Maison published this article in The Journal of Clinical Endocrinology in 2004(vol 89 pp 2192-2199). He found that the use of low dose human growth hormone will increase lean body, decrease percent body fat, decrease the total cholesterol and the “bad” LDL cholesterol, as well as decrease diastolic blood pressure. Another important study by Juul(Circulation 106(2002) 939-944) demonstrated that when comparing patients in the lower 25% of the reference range of IGF-1(growth hormone metabolite) to patients in the upper 25% of the reference range that there was a two fold higher risk of ischemic heart disease in the lower group. Prospective studies have repeatedly identified a higher risk of ischemic heart disease and congestive heart failure in the growth hormone deficient patients in the lower 50th percentile of normal.

The classic profile for a Growth Hormone deficient patient may include increased central obesity, increased body fat, decreased lean mass, decreased energy, and exercise performance, altered lipid profile with low HDL’s (good type), high LDL’s (bad type) high total cholesterol. In addition, these patients often show early diabetes with evidence of Insulin Resistance. Patients with compromised lung function also demonstrated improvement with therapy. These patients almost universally have higher risks of cardiovascular morbidity/mortality, poor quality of life with more depression / neurodegenerative diseases, and metabolic deterioration. Medicine is very aggressive to manage already existing diseases. If we know ahead of time that we can dramatically reduce these disease processes than I firmly believe that physicians should intervene with the progressive depletion of human growth hormone. It is not about being a taller person, but it is about being a healthier individual, and doing everything we can do to proactively protect ourselves, and thus improve the quality of our lives.