Gastrointestinal Distress after Creatine Supplementation in Athletes: Are Side Effects Dose Dependent?
Ostojic SM, Ahmetovic Z
Evidence is still building up
Summary
An RCT in 59 top-level male soccer players compared creatine 10 g/day taken as 2×5 g split doses versus a single 10 g dose versus placebo over 28 days. Diarrhea incidence was 28.6% in the split-dose group versus a significantly higher 55.6% in the single 10 g dose group (35.0% in placebo). Even within the recommended daily amount, larger single servings raise the risk of GI distress.
Key findings
- 1
Diarrhea incidence was 28.6% with 2×5 g split dosing versus a significantly higher 55.6% with a single 10 g dose (p<0.05)
- 2
Reported GI symptoms, in order of frequency, were diarrhea (39.0%), stomach upset (23.8%), and belching (16.9%)
- 3
Concluded no serious harm to the GI tract from short-term use within the recommended 10 g/day, but splitting doses reduced GI symptoms
- 4
Conducted in 59 top-level male soccer players; extrapolation to general trainees warrants some caution
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