Vitamins, Minerals and Dietary Supplements
What is creatine? Why do we need it?
Creatine is a well-known dietary supplement. Also known as creatine monohydrate, it is produced by the human body, present in muscle tissues, and used in the production of phosphocreatine, an important component in the formation of ATP, which is responsible for a wide range of metabolic processes. Supplementing with creatine will increase phosphocreatine levels in muscle, especially when those people exercise or take large amounts of carbohydrates.
Creatine is a popular supplement among athletes. Evidence has shown that creatine supplements may lead to increases in lean body mass following exercise. In particular, it appears to improve performance and prevents the onset of muscle fatigue during periods of high-intensity exercise such as weight lifting. However, these gains appear to be effective only for short periods of time
Creatine may be effective in treating other health conditions as well. Intravenous injections of creatine may improve heart function in people with congestive heart failure. Large amounts of creatine may also reduce total cholesterol and triglyceride levels in both men and women.
How much creatine should I take?
There are two popular methods used for supplementing with creatine. In the first method, known as "loading," people take 20 grams of creatine per day (mixed with warm liquid and taken in four amounts) for five to six days, followed by two to 10 grams per day, for short-term gains in muscle mass. In the second method, smaller amounts (three grams per day) are taken over a period of four weeks, which provides extended levels of creatine in the muscles. Some studies have shown that taking creatine with sugar appears to maximize the effect of the supplement.
What forms of creatine are available?
Creatine is produced naturally in the human liver, kidneys and pancreas. It can also be obtained through food sources such as fish. Supplements are also available as powders, pills, capsules and tablets.
What can happen if I take too much creatine? Are there any interactions I should be aware of? What precautions should I take?
While creatine is not toxic, some minor side-effects may be reported, including diarrhea and muscle cramping. In addition, a case study published in 1999 reported an incidence of interstitial nephritis, a debilitating kidney condition, in a patient who was taking 20 grams of creatine per day; the patient's kidney function improved following discontinuance of creatine. As such, creatine should be avoided by patients with existing kidney diseases.
As of this writing, there are no well-known drug interactions associated with creatine. As always, make sure to consult with a licensed health care provider before taking creatine or any other herbal remedy or dietary supplement.
- Andrews R, Greenhaff P, Curtis S, et al. The effect of dietary creatine supplementation on skeletal muscle metabolism in congestive heart failure. Eur Heart J 1998;19:617-22.
- Koshy KM, Griswold E, Schneeberger EE. Interstitial nephritis in a patient taking creatine. N Engl J Med 1999;340:814-5
- Peyrebrune MC, Nevill ME, Donaldson FJ, et al. The effects of oral creatine supplementation on performance in single and repeated sprint swimming. J Sports Sci 1998;16:271-9.
- Rawson ES, Clarkson PM. Acute creatine supplementation in older men. Int J Sports Med 2000;21:71-5.
- Tarnopolsky M, Martin J. Creatine monohydrate increases strength in patients with neuromuscular disease. Neurology 1999;52:854-7.