Risk assessment for creatine monohydrate.
Level 5 - mechanism / opinion, no new human data
Narrative review and toxicological risk assessment framework without formal systematic review or meta-analysis
PubMed 16814437 · doi:10.1016/j.yrtph.2006.05.005
What was done
Authors conducted a safety risk assessment on creatine monohydrate supplementation using existing human and animal literature. Human data analyzed included acute high-dose protocols (~20 g/day for ≤1 week), chronic lower-dose protocols (3–5 g/day for up to 1 year), and combination regimens. The applicability of standard Upper Level of Intake (UL) criteria was evaluated against Observed Safe Level (OSL) and Highest Observed Intake (HOI) methods.
What was found
The abstract reports no raw numerical effect sizes or safety endpoints. Based on the OSL risk assessment framework, safety evidence was determined to be strong for chronic supplementation up to 5 g/day, establishing this intake as the OSL. While higher acute doses showed no adverse effects, data were deemed insufficient to establish long-term safety above 5 g/day.
Why it matters
This evaluation establishes a formal Observed Safe Level of 5 g/day for chronic creatine monohydrate intake within sports nutrition and supplement regulatory frameworks.
Limits
The abstract omits the number of studies reviewed, sample sizes, and specific clinical or biochemical parameters assessed, and notes insufficient data to determine chronic safety for doses above 5 g/day.
Cited by
- supports Long-term studies demonstrate that taking 5 grams of creatine monohydrate per day for years is safe.