From the Guidelines
L-creatine supplementation is not recommended for individuals with pre-existing kidney disease, as it may exacerbate kidney problems, but for healthy individuals, the risk of harm is low when used as directed. When considering the use of L-creatine, it is essential to weigh the potential benefits against the potential harms, particularly for individuals with pre-existing kidney disease. According to a study published in the American Journal of Kidney Diseases 1, the use of dietary supplements, including L-creatine, can influence changes in blood pressure and may lead to nephrotoxicity in certain individuals. Some key points to consider when using L-creatine supplementation include:
- The potential for digestive issues, such as stomach pain, nausea, diarrhea, and muscle cramps
- The risk of water retention, which can cause temporary weight gain and bloating
- The potential for kidney concerns, particularly for those with pre-existing kidney disease
- The importance of consulting a healthcare provider before using L-creatine, especially for individuals with kidney problems
- The potential for interactions with medications that affect kidney function, including NSAIDs like ibuprofen when used chronically at high doses It is crucial to note that the study published in the American Journal of Kidney Diseases 1 found that the use of creatine supplementation in a patient with a solitary kidney did not alter kidney function, but creatinine clearance measurements were incorrect, leading to a misclassification of acute kidney injury. Therefore, healthy individuals can use L-creatine supplementation with a low risk of harm when used as directed, but it is essential to be aware of the potential side effects and interactions.
From the Research
Potential Harms of L-Creatine
- The most common adverse effect of creatine supplementation is transient water retention in the early stages of supplementation 2.
- There have been cases of liver and renal complications with creatine when combined with other supplements or taken at higher than recommended doses for several months 2.
- Short- and long-term creatine supplementation had no significant effects on kidney function in healthy athletes and bodybuilders with no underlying kidney diseases 3.
- However, it is advisable that creatine supplementation not be used by individuals with pre-existing kidney disease or those with a potential risk for kidney dysfunction 3.
- Creatine supplementation may be associated with an increased risk of renal dysfunction in people with a history of renal disease or those taking nephrotoxic medications 4.
- Gastrointestinal disturbances and muscle cramps have been reported occasionally in healthy individuals, but the effects are anecdotal 5.
- Liver and kidney dysfunction have also been suggested on the basis of small changes in markers of organ function and of occasional case reports, but well-controlled studies on the adverse effects of exogenous creatine supplementation are almost nonexistent 5.