|Creatine: Not Just a Sports Nutrition Supplement|
By Will Brink
Readers of the March 2003 issue of Life Extension magazine should recall the long list of potential medical, performance and anti-aging effects of creatine. The article outlined the substantial body of research that found creatine may help with diseases effecting the neuro muscular system, such as muscular dystrophy and may have therapeutic applications in aging populations, wasting syndromes, muscle atrophy, fatigue, myopathies, Parkinson’s disease, Huntington’s disease and other mitochondrial cytopathies. Several studies have shown it may reduce cholesterol by up to 15% and has been used to correct certain inborn errors of metabolism, such as people born without the enzyme(s) responsible for making creatine.
The article also covered exactly what creatine is, how it works and how much is required to possibly treat the aforementioned pathologies. If you missed that article, refer to the March 2003 issue of Life Extension magazine, or view it at www.lef.org. In this article, we examine some additional properties of creatine, such as its effects on growth hormone release, homocysteine and chronic fatigue syndrome, as well as other important issues surrounding this supplement, such as its safety.
Although data is limited, some research suggests creatine can raise growth hormone equal to that of intense exercise. Growth hormone (GH) is known to play an essential role in the regulation of body fat levels, immunity, muscle mass, wound healing, bone mass and literally thousands of other functions both known and yet unknown. It is well established that GH levels steadily decline as we age and is partially responsible for the steady loss of muscle mass, loss of skin elasticity, immune dysfunction and many other physical changes that take place in the aging human body. Therefore, the possible effects of creatine on GH is worth exploring in aging populations.
One study found creatine could mimic the increased GH levels seen after intense exercise.1 In this comparative cross-sectional study, researchers gave six healthy male subjects 20 grams of creatine in a single dose at resting (non-exercising) conditions. The study found that all subjects showed a “significant” increase of GH in the blood during the six-hour period after creatine ingestion. However, the study also found “a large interindividual variability in the GH response.” That is, there were wide differences among individuals in the levels of GH achieved from taking the creatine. For the majority of subjects the maximum GH concentration occurred between two and six hours after ingesting the creatine. The researchers concluded “In resting conditions and at high dosages creatine enhances GH secretion, mimicking the response of strong exercise which also stimulates GH secretion.” These researchers felt that the effects of creatine on GH could be viewed as one of creatine’s anabolic properties with the lean mass and strength increases observed after creatine supplementation. Although creatine supplementation has been found to increase lean muscle mass and strength in many studies, the effects of creatine on those tissues via GH enhancement has yet to be elucidated.
Creatine may reduce homocysteine levels
Creatine and chronic fatigue/fibromyalgia
Creatine safety issues: fact or fiction?
In some, but not all people, creatine can raise a metabolic byproduct of creatine metabolism known as creatinine. Some people–including some medical professionals who should know better–have mistakenly stated that elevated levels of creatinine could damage the kidneys. Elevated creatinine is often a blood indicator, not a cause, of kidney dysfunction. That’s a very important distinction, and several short- and long–term studies have found creatine supplements have no ill effects on the kidney function of healthy people.9,10 Though it makes sense that people with pre-existing kidney dysfunction should avoid creatine supplements, it is reassuring to know that creatine supplements were found to have no ill effects on the kidney function of animals with pre-existing kidney failure, showing just how non toxic creatine appears to be for the kidneys.11 Bottom line, creatine safety has been extensively researched and is far safer than most over-the-counter (OTC) products, including aspirin.
About Will Brink
1. Schedel JM, et al. Acute creatine loading enhances human growth hormone secretion. J Sports Med Phys Fitness 2000 Dec;40(4):336-42
2. Wyss M, et al. Health implications of creatine: can oral creatine supplementation protect against neurological and atherosclerotic disease? Neuroscience 2002;112(2):243-60.
3. Stead LM, et al. Methylation demand and homocysteine metabolism: effects of dietary provision of creatine and guanidinoacetate. Am J Physiol Endocrinol Metab 2001 Nov;281(5):E1095-100.
4. Park JH, et al. Use of P-31 magnetic resonance spectroscopy to detect metabolic abnormalities in muscles of patients with fibromyalgia. Arthritis Rheum 1998 Mar;41(3):406-13.
5. Kreider RB, et al. Long-term creatine supplementation does not significantly affect clinical markers of health in athletes. Mol Cell Biochem 2003 Feb;244(1-2):95-104.
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7. Poortmans JR, et al. Adverse effects of creatine supplementation: fact or fiction? Sports Med 2000 Sep;30(3):155-70.
8. Terjung RL, et al. American College of Sports Medicine roundtable. The physiological and health effects of oral creatine supplementation. Med Sci Sports Exerc 2000 Mar;32(3):706-17.
9. Poortmans JR, et al. Long-term oral creatine supplementation does not impair renal function in healthy athletes. Med. Sci. Sport. Exerc. 31:1108-1110, 1999.
10. Mihic S, et al. Acute creatine loading increases fat-free mass, but does not affect blood pressure, plasma creatinine or CK activity in men and women. Med Sci Sports Exerc 2000 Feb;32(2):291-6.
11. Taes YE, et al. Creatine supplementation does not affect kidney function in an animal model with pre-existing renal failure. Nephrol Dial Transplant 2003 Feb;18(2):258-64.
|Additional references of interest:|
Field ML. Creatine supplementation in congestive heart failure. Cardiovasc Res 1996 Jan;31(1):174-6.
Pearson DR, et al. Long-term effects of creatine monohydrate on strength and power. Journal of Strength and Conditioning Research, 13(3); 187-192, 1999.
Odland LM, et al. Effect of oral creatine supplementation on muscle [PCr] and short-term maximum power output. Med-Sci-Sports-Exerc. 1997 Feb; 29(2): 216-9.
Earnest CP et al. High-performance capillary electrophoresis-pure creatine monohydrate reduces blood lipids in men and women. Clin-Sci-Colch. 1996 Jul; 91(1): 113-8.
Peeters B, et al. Effect of oral creatine monohydrate and creatine phosphate supplementation on maximal strength indices, body composition and blood pressure. Journal of Strength and Conditioning Reserach.
Kreider RB, et al. Effects of creatine supplementation on body composition, strength and sprint performance. Medicine and Science in Sports and Exercise 1998;30(1): 73-82.