Creatine Supplementation Dose and Duration Are Not Associated with Increased Side Effects: A Structured Review and...

Area of Science:

• Sports Medicine
• Nutritional Science
• Supplement Safety

Background:

• Concerns exist regarding potential side effects of high-dose or long-term creatine monohydrate supplementation (CrM).
• Previous research has not conclusively determined if dose or duration influences adverse event occurrence.

Purpose of the Study:

• To investigate the association between creatine monohydrate (CrM) dosage and duration of use with the incidence of side effects (SEs).
• To evaluate the safety profile of CrM across various dosing regimens and supplementation periods.

Main Methods:

• Analysis of data from 684 randomized clinical trials, including over 12,800 participants in CrM and placebo groups.
• Categorization of SEs and grouping of CrM dose and duration into tertiles (low, moderate, high).
• Statistical analysis using crosstabs, chi-square tests, and logistic regression, adjusted for covariates.

Main Results:

• Reported SEs were infrequent across all analyzed trials.
• While statistical associations were found between dose/duration tertiles and SE reporting, effect sizes were small and events mild.
• No consistent dose- or duration-dependent increase in SE risk was observed; placebo groups sometimes reported higher SE frequencies.

Conclusions:

• Creatine monohydrate (CrM) appears to be well-tolerated, with no increased risk of SEs compared to placebo, irrespective of dose or duration.
• The study found no clinically meaningful risk associated with high-dose or long-term CrM supplementation.
• Findings support the general safety of CrM for various populations and usage patterns.