Linford Christie and Sally Gunnell won gold medals in the 1992 Barcelona Summer Games after taking creatine. Since that time, many athletes and body builders routinely take creatine to build muscle. Even the Olympic Committee approves of this supplement. Although researchers initially thought creatine might damage the kidneys of healthy people, subsequent studies, such as the one appearing in the February 2003 issue "Molecular Cell Biochemistry," repeatedly indicate that it is safe. However, this finding does not extend to patients who have kidney disease.
Creatine and Creatinine
Creatine is an amino acid synthesized in the liver from the amino acids glycine, arginine and methionine. After it is transported to muscle tissue, it helps the muscle provide energy. Eventually, it breaks down as a result of muscular activity and becomes the waste product creatinine. Creatinine is used as a marker for kidney disease because while healthy kidneys quickly remove creatinine from the blood, diseased kidneys cannot perform this function.
Low-Protein Diet
The National Kidney Foundation recommends that kidney patients with elevated urine protein levels follow a low-protein diet. Creatine is an amino acid and as such, it is a building block for making protein. Taking creatine is inconsistent with the goals of a low-protein diet. High urine protein accelerates the progression of kidney disease. A diet low in protein slows down the progression of kidney disease. Patients should not embark on a low-protein diet without talking to their nephrologists because this recommendation does not apply to all patients.
Recommendations
Both MedlinePlus and MayoClinic.com recommend avoiding creatine supplements if you have kidney disease. Given that kidney damage is not reversible, putting the kidneys at greater risk by taking this supplement is an unwise practice for athletes and body builders.
Drug Interactions
Kidney patients often take many different drugs, such as blood pressure medication and immunosuppressants, to manage the symptoms of kidney disease. MedlinePlus particularly warns against taking creatine if you take cyclosporine, gentamicin, tobramycin, ibuprofen, indomethacin and naproxen, among others. The combination of such drugs increased the likelihood of accelerating kidney damage because these drugs are nephrotoxic.
References
- MedlinePlus; Creatine; Jan. 10, 2011
- MayoClinic.com; Creatinine; July 2011
- University of Maryland Medical Center; Creatine; Steven D. Ehrlich, NMD; June 2, 2009
- National Review of Medicine: Supplement Muscles in on the Market; Marlene Busko; July 2004
- "Molecular Cell Biochemistry"; Long-Term Creatine Supplementation does not Significantly Affect Clinical Markers of Health in Athletes; R.B. Kreider, et al.; February 2003
