From the Guidelines
Creatine supplementation is not recommended for individuals with pre-existing kidney conditions, as it may lead to incorrect measurements of kidney function and potentially worsen kidney health. The use of creatine supplementation in individuals with a solitary kidney has been shown to not alter kidney function, but it can lead to incorrect measurements of creatinine clearance, which can misclassify acute kidney injury 1. Additionally, certain dietary supplements, including creatine monohydrate, have been associated with nephrotoxicity, although the mechanism and causality are not always clear 1.
When considering creatine supplementation, it is essential to weigh the potential benefits against the potential risks, particularly for individuals with pre-existing kidney conditions. The recommended dosing protocol for creatine supplementation is typically 3-5 grams of creatine monohydrate daily, taken consistently, although this may need to be adjusted for individuals with kidney disease 1. It is also crucial to monitor kidney function regularly, using serum creatinine and estimated glomerular filtration rate (eGFR) measurements, to detect any potential decline in kidney function 1.
Some key points to consider when using creatine supplementation include:
- The potential for incorrect measurements of kidney function, particularly in individuals with a solitary kidney
- The risk of nephrotoxicity associated with certain dietary supplements, including creatine monohydrate
- The importance of monitoring kidney function regularly, using serum creatinine and eGFR measurements
- The need to adjust the dosing protocol for individuals with pre-existing kidney conditions
- The potential benefits of creatine supplementation for improving exercise performance, particularly for high-intensity, short-duration activities.
Overall, while creatine supplementation can be beneficial for exercise performance, it is crucial to approach its use with caution, particularly for individuals with pre-existing kidney conditions, and to prioritize monitoring of kidney function to minimize the risk of adverse effects.
From the Research
Creatinine Supplementation Effects
- The effects of creatine supplementation on kidney function have been studied extensively, with most research indicating no significant adverse effects on healthy individuals 2, 3, 4.
- Studies have shown that short- and long-term creatine supplementation does not impair kidney function in resistance-trained individuals consuming a high-protein diet 4.
- However, it is recommended that individuals with pre-existing kidney disease or those at risk for kidney dysfunction should avoid creatine supplementation 2.
- A high-protein diet, which is often associated with creatine supplementation, may cause glomerular hyperfiltration, a potentially maladaptive response that could accelerate kidney disease progression 5.
- Creatine supplementation has been shown to have various health and therapeutic benefits, including enhanced exercise capacity, postexercise recovery, and potential neurologic benefits 3, 6.
Safety and Tolerance
- Creatine supplementation is generally considered safe and well-tolerated in healthy individuals, with no significant differences in kidney function observed between creatine and placebo groups 4.
- Short-term high-dose oral creatine supplementation may stimulate the production of methylamine and formaldehyde, but there is currently no definitive clinical evidence of adverse effects on kidney function 2.
- Long-term creatine supplementation has been shown to be safe and effective in promoting health and therapeutic benefits, particularly in individuals with metabolically stressed states or limited oxygen availability 6.