The brain produces and releases growth hormones for development and repair of cells. In 1996, the U.S. Food and Drug Administration approved the use of growth hormone injections for adults diagnosed with growth hormone deficiency. Because of safety and effectiveness considerations, growth hormone is not approved for anti-aging effects, general obesity or sports performance.
Growth Hormone Function
Growth hormone stimulates production of an insulin-like growth factor that stimulates cell development. Higher growth hormone levels in children and teens stimulate development and growth. Blood levels of insulin-like growth factor decrease as people age or become obese. Testing can confirm growth hormone deficiency because other medical conditions, including liver or kidney failure, untreated inactive thyroid, or malnutrition might be the cause of low level of insulin-like growth factor.
Growth Hormone Deficiency
According to the American Association of Clinical Endocrinologists, adults with growth hormone deficiency develop metabolic complications with reduced skeletal muscle, lean body mass and increased fat mass. Fat mass is especially troubling in the abdominal area because it will raise the risk of increased risk of cardiovascular disease associated with type II diabetes and altered lipid metabolism.
Growth Hormone Replacement
The body's level of growth hormone peaks around midnight. To mimic normal release injections work best given each evening. Physicians individualize the dose for the patient. According to the American Association of Clinical Endocrinologists, women may need additional growth hormone because estrogen, hormone replacement therapy and contraceptives interfere with growth hormone function. By comparison, males may need a lower dose of growth hormone because testosterone can increase growth hormone function.
Muscle and Fat Tissue
Abdominal fat correlates with low serum growth hormone levels. A study published in International Journal of Obesity in December 2008, suggests a growth hormone supplementation for individuals with growth hormone deficiency decreases body fat and leptin, which is the hormone stimulating fat storage. According to a mouse study published in the Journal of Nutrition, growth hormone injections administered with a normal diet produced a gain in muscle mass during initial period of growth recovery after prolonged food restriction in comparison to diet alone that increased fat deposits.
A review of research published in the Journal of Clinical Endocrinology & Metabolism showed growth hormone converted fat tissue into lean body mass without significant weight loss. Metabolic improvements included decreased cholesterol levels, changes in percent of body fat, increase in muscle and a decrease in abdominal fat. A study published in Journal of the American Medical Association ” in November 2002, showed an increase in lean body mass and a decrease in body fat in both men and women ages 65 to 88 with growth hormone injections.
Growth Hormone Injection Side-effects
The injection sites should be rotated to reduce bruising and pain. Side effects associated with growth hormone injections include an increase in fasting blood glucose, diabetes and swelling from fluid accumulation in skin and tissues. According to a study published in Journal of the American Medical Association” 18-year-old male participants treated with human growth hormone developed glucose intolerance or diabetes. All side effects experienced by study participants went away within two to six after stopping growth hormone.
- "Journal of the American Medical Association"; Growth Hormone and Sex Steroid Administration in Healthy Aged Women and Men -- A Randomized Controlled Trial; MR Blackman et al; Nov. 13, 2002
- "The Journal of Nutrition"; Growth Hormone Promotes Somatic and Skeletal Muscle Growth Recovery in Rats Following Chronic Protein-Energy Malnutrition; TA Gautsch, SM Kandl, SM Donovan and DK Layman; April 1999