Effect of creatine supplementation on measured glomerular filtration rate in postmenopausal women.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 21574777 · doi:10.1139/h11-014
What was done
Postmenopausal women (mean age 58 ± 3 years) were randomly assigned to receive either creatine supplementation (20 g·day(-1) for 1 week followed by 5 g·day(-1) thereafter) or a placebo for 12 weeks. Renal function was assessed by directly measuring glomerular filtration rate via [(51)Cr]EDTA clearance at baseline and after 12 weeks.
What was found
[(51)Cr]EDTA clearance remained unchanged between groups (Creatine group: baseline 86.16 ± 14.36 mL·min(-1) per 1.73 m(2), post-intervention 87.25 ± 17.60 mL·min(-1) per 1.73 m(2); Placebo group: baseline 85.15 ± 8.54 mL·min(-1) per 1.73 m(2), post-intervention 87.18 ± 9.64 mL·min(-1) per 1.73 m(2); p = 0.81).
Why it matters
Using direct isotopic measurement of glomerular filtration rate rather than serum creatinine estimates, this trial demonstrates that standard creatine loading and maintenance dosing does not impair kidney function in postmenopausal women over 12 weeks.
Limits
The abstract does not report the total sample size (n). The trial was limited to 12 weeks of follow-up in healthy postmenopausal women, so findings may not generalize to longer durations or populations with pre-existing renal disease.
Cited by
- supports Creatine supplementation does not adversely affect renal, liver, or cardiovascular cells, even at dosages of 11 grams per day in postmenopausal females.