Growth hormone is a protein hormone (not a steroid hormone) produced and secreted by the pituitary gland in the brain. After age 30, growth hormone secretion declines by approximately 14 percent per decade.
The decline in IGF-1 blood levels as we age has been shown to contribute to many aspects of aging, including thinning of our skin, more rapid wrinkling, brittle hair, and nails, grayed or dulled hair color, reduced energy, loss of muscle and bone mass, decreased libido and sexual performance ability, increased body fat, and other common signs and symptoms of aging. Conversely, growth hormone injections and/or supplementation with natural agents that stimulate the release of growth hormone have been shown to boost IGF-1 blood levels back to more youthful levels and reverse many age-related changes in the body. Studies have shown that boosting IGF-1 blood levels back to more youthful levels leads to a multitude of anti-aging benefits, including:
- improved immune function;
- increased sexual potency and function;
- increased muscle strength, muscle mass and energy;
- decreased body fat;
- elevated mood;
- improved sleep patterns;
- improved memory;
- improved skin thickness, texture, and reduced wrinkle lines;
- restoration of hair color; and
- improved vision.
The most pronounced anti-aging effects have been seen in patients whose IGF-1 blood levels were returned to a level at or greater than 350ng/ml, which certain anti-aging doctors claim can single-handedly reverse aging by up to 20 years in older subjects. To achieve blood levels in this range, regular injections of growth hormone are required by a physician trained in anti-aging medicine.
However, growth hormone injections have been shown to cause side-effects, especially in subjects whose IGF-1 returned to levels approaching 400ng/ml. The most common side-effects include swelling of the feet, fluid retention, joint pains, carpal tunnel syndrome, and more rarely, allergic responses.
I am concerned about boosting IGF-1 blood levels above 290-300ng/ml, as a number of research papers have correlated higher IGF-1 levels with an increased risk for breast and prostate cancer. This doesn't necessarily mean that IGF-1 causes cancer, but it does imply that more research is required before we can state with certainty that growth hormone injections are a completely safe anti-aging intervention.
Growth Hormone Secretagogue Supplements: A Safer, Natural Alternative
A number of studies have revealed that a combination of certain amino acids, ingested orally as a supplement at specific dosages, can stimulate the pituitary gland to release greater quantities of growth hormone after the age of 40, elevating our IGF-1 blood levels to match those we experienced up to our mid-30s. Studies show that supplementation with these amino acid combinations, collectively known as growth-hormone secretagogues, can raise IGF-1 blood levels up to 275ng/ml, which may be a safer level than 350-400ng/ml.
In a three-month study involving a proven growth hormone secretagogue supplement, blood levels of IGF-1 increased by 30% on average by the end of the 12th week, and patient self-assessment scores indicated that, of the 36 participants, 58% noted improvement in muscular strength; 42% reported an increase in muscle size; 68% reported body fat reduction; 74% noted an increase in energy; 47% reported improvements in skin texture; 32% reported improved skin thickness; 37% reported reduction in wrinkles (disappearance or reversal); 21% reported improvement in general healing capacity; 37% reported improvement in joint and back flexibility; 47% felt their immune system was stronger; 32% reported improved sexual potency; 44% of men reported better sexual stamina (penile erection); 66% of men reported less frequent nighttime urination; 53% reported improved mental energy and clarity; 37% reported improved attitude and mood elevation; and 47% reported improvement in memory. In male subjects, there was a reduction in PSA blood levels (prostate-specific antigen), signifying that this intervention did not trigger prostate malignancy or enlargement. As well, blood sugar levels in diabetic subjects were shown to improve, and there was also improvement in both cardiac (heart) and pulmonary (lungs) tests during the course of the three-month trial.
The author of the study, D.M. Ladley, MD, also noted that blood pressure was better controlled and improvement in menopausal symptoms was reported among affected women in this age group. Dr. Ladley, an authority on the use of growth hormone secretagogues, elaborated that improved energy, endurance, muscle mass and strength, and reduced body fat, were among the most frequently reported benefits in the first four weeks of supplementation. New hair growth, restoration of hair color, thickening of the skin, and disappearance of skin discoloration generally occurred between the eighth and 12th weeks, with continued improvement beyond the 12-week term. There were no side-effects reported from the use of the growth hormone secretagogue by any of the participants in this study. (Growth hormone secretagogues are generally well- tolerated and no consistent reports of adverse side-effects have been reported.)
In the study, initial blood levels of IGF-1 ranged from 21-276ng/ml. Subjects with lower values appeared to have experienced the largest increases in IGF-1 blood levels with secretagogue supplementation. As a rule, growth hormone secretagogue supplementation cannot elevate blood levels of IGF-1 beyond 275ng/ml. Thus, before beginning a supplementation program with a growth hormone secretagogue, you should first have your blood levels of IGF-1 evaluated.
What Supplements Qualify?
Unfortunately, the growth hormone secretagogue industry is filled with unproven, ineffective and/or scam products that are not worth spending your money on. Individuals can assemble their own growth hormone secretagogue by stacking several amino acids together and taking them at once, one hour before bedtime. Growth-hormone and anti-aging specialist Vincent Giampapa, MD (medical director of the Longevity Institute International in Montclair, N.J.), suggests a starter amino-acid stack program consisting of:
- Arginine - 2 grams
- Ornithine - 2 grams
- Lysine - 1 gram
- Glutamine - 1 gram
After an initial course of one month, increase all of the amino acids in the stack by 2 grams each. Growth hormone secretagogue supplements are usually taken for five consecutive days, followed by two days with no supplementation, and then five days on again, repeating this sequence.
It is advisable to have your IGF-1 levels checked after three months of growth hormone secretagogue supplementation, in order to see how much of an increase has occurred in this hormone, and to gauge the extent of its anabolic and other anti-aging effects.
- Amato G, Carella C, Fazio S, et al. Body composition, bone metabolism, and heart structure and function in growth hormone (GH)-deficient adults before and after GH replacement therapy at low doses. Journal of Clinical Endocrinology and Metabolism 1993;77:1671-1676.
- Bengtsson BA, Eden S, Lonn L, et al. Treatment of adults with growth hormone (GH) deficiency with recombinant human GH. Journal of Clinical Endocrinology and Metabolism 1993;76;309-317.
- Bengtsson BA. The consequences of growth hormone deficiency in adults. Acta Endocrinologica 1993;128(Suppl 2):2-5.
- Cummings DE, et al. Age-related changes in growth hormone secretion: should the somatopause be treated? Sem Reproductive Endo 1999;17(4):311-326.
- Cuneo RC, Salomon F, Wiles CM, et al. Growth hormone treatment in growth hormone deficient adults. II. Effects on exercise performance. Journal of Applied Physiology 1991;70:695-700.
- Fuh VL, Bach MA. Growth hormone secretagogues: mechanism of action and use in aging. 1998 Merck Research Laboratories. Growth Horm IGF Res 1998 Feb; 8m1:13-20.
- Jamieson J and Dorman L.E. The Role of Somatotroph-Specific Peptides and IGF-1 Intermediates as an Alternative to HGH Injections. Presented for the American College for Advancement in Medicine, Oct. 30, 1997.
- Jamieson J, Dorman L. Growth Hormone: Reversing Human Aging Naturally. Longevity News Network 1997.
- Johnston DG, Bengtsson BA. Workshop report: the effects of growth hormone and growth hormone deficiency on lipids and the cardiovascular system. Acta Endocrinologica 1993;128 (Suppl 2):69-70.
- Klatz R. Grow Young With HGH. Harper Perennial, 1998.
- Ladley D.M. The Role of Oral Growth Hormone Secretagogues in Anti- Aging Therapy. Presented at the European International Conferences on Quality of Life and Longevity Medicine (Sept. 28-30, 1998).
- McGauley GA, Cuneo RC, Salomon F, et al. Psychological well-being before and after growth hormone treatment in adults with growth hormone deficiency. Hormone Research 1990;33(suppl 4):52-54.
- O'Halloran DJ, Tsatsoulis A, Whitehouse RW , et al. Increased bone density after recombinant human growth hormone (GH) therapy in adults with isolated GH deficiency. Journal of Clinical Endocrinology and Metabolism 1993;76:1344-1348.
- Rudman D, et al. Effects of human growth hormone in men over 60 years old. N Engl J Med 1990;323(1):1-6.
- Salomon F, Cuneo RC, Hesp R, et al. The effects of treatment with recombinant human growth hormone on body composition and metabolism in adults with growth hormone deficiency. New England Journal of Medicine 1989;321:1797-1803.
- Stanford University Medical Center Many effects of aging can now be reversed, bring about dramatic rejuvenating results in older people. Psycho-Neuro Endocrinology 1992;17(4).
- Veldhuis JD. Endocrinology of aging. Medscape Diabetes and Endocrinology 2000;2(1).
James Meschino, DC, MS
Toronto, Ontario Canada
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