From the Guidelines
Creatine supplements can temporarily affect eGFR measurements but do not actually harm kidney function in healthy individuals. When you take creatine supplements, they can cause a harmless increase in serum creatinine levels, which is one of the markers used to calculate eGFR, as seen in a controlled single-patient study where a 20-year-old man who had undergone a unilateral nephrectomy received 20 g of creatine monohydrate supplementation per day, resulting in a change in serum creatinine level from 1.03 mg/dL before creatine supplementation to 1.27 mg/dL after, but no difference in 51 Cr-EDTA clearance measurement 1. This can make it appear as though kidney function has decreased when it actually hasn't.
Key Points to Consider
- The effect of creatine supplementation on eGFR measurements is temporary and harmless, and it is essential to inform healthcare providers about creatine use before kidney function tests to avoid misleading results.
- People with pre-existing kidney disease should consult with their healthcare provider before using creatine supplements, as the impact of creatine on kidney function in individuals with kidney disease is not well understood.
- The use of dietary supplements, including creatine, may affect the assessment of GFR by alteration of exogenous creatinine generation, and healthcare providers should be aware of this potential impact when evaluating kidney function in individuals taking creatine supplements 1.
Recommendations for Clinical Practice
- Healthcare providers should consider the potential impact of creatine supplementation on eGFR measurements when evaluating kidney function in healthy individuals.
- Individuals taking creatine supplements should inform their healthcare providers about their supplement use before undergoing kidney function tests.
- People with pre-existing kidney disease should consult with their healthcare provider before using creatine supplements to discuss the potential risks and benefits.
From the Research
Creatine Supplement and eGFR
- The effect of creatine supplements on estimated glomerular filtration rate (eGFR) is a topic of interest, with several studies investigating its potential impact on renal function.
- A study published in 2019 2 found that creatine supplements may transitorily rise serum creatinine levels, which could lead to an overestimation of chronic renal failure, but concluded that creatine supplements are safe and do not cause renal disease.
- Another study from 2018 3 reviewed available data on the renal safety of creatine supplementation and found no significant effects on eGFR in healthy athletes and bodybuilders with no underlying kidney diseases.
- A systematic review and meta-analysis published in 2019 4 also found that creatine supplementation did not significantly alter serum creatinine levels or plasma urea values, indicating no renal damage.
Renal Function and Creatine Supplementation
- The studies suggest that creatine supplementation is safe for individuals without underlying kidney diseases, but it is advisable to avoid its use in people with pre-existing kidney disease or those with a potential risk for kidney dysfunction 3, 4.
- A study from 2012 5 discussed the benefits of exercise in individuals with chronic kidney disease (CKD) and found that exercise training results in improved physical performance and functioning, with no worsening of kidney function reported.
- However, a study from 2014 6 highlighted the importance of safety considerations when using ACE inhibitors in patients with CKD, emphasizing the need for careful management of potential adverse effects.
Key Findings
- Creatine supplementation does not appear to have a significant impact on eGFR in healthy individuals 3, 4.
- However, individuals with pre-existing kidney disease or those at risk for kidney dysfunction should exercise caution when using creatine supplements 3, 4.
- Further research is needed to fully understand the effects of creatine supplementation on renal function in various populations 2, 3, 4.