Creatine and Cognition

What the meta-analyses report on memory

Two systematic reviews with meta-analysis have pooled randomized controlled trials examining creatine supplementation and memory. A meta-analysis of randomized controlled trials in healthy individuals reported that creatine improved measures of memory compared with placebo, with a small standardized mean difference of about 0.29. A separate systematic review and meta-analysis in adults reported a similar small positive effect on memory, with a standardized mean difference of about 0.31 and a GRADE certainty rated as moderate. The doses studied across these trials spanned roughly 2.2 to 20 g per day over intervention periods ranging from several days to several months.^{[1], [2]}

These pooled effects are statistically significant but small in magnitude, and the underlying trials showed substantial heterogeneity, meaning results varied considerably from study to study. This variability, together with the modest effect sizes, is an important caveat when interpreting the memory findings.^{[1], [2]}

Who may benefit and in which domains

Subgroup analysis suggests the memory benefit is not uniform across the population. In one meta-analysis the improvement in memory was significant in older adults aged 66 to 76 years, with a notably larger effect, while younger adults aged 11 to 31 years showed no significant change. A second meta-analysis likewise reported that certain subgroups, including some clinical and middle-aged populations, appeared to benefit more, partially supporting the idea that age and baseline status influence the response.^{[1], [2]}

Beyond memory, the picture is more mixed. Pooled analysis found no significant effect of creatine on overall cognitive function or executive function, while signals for attention and information processing speed were of low certainty. This means that any cognitive role for creatine, where present, is currently best characterized for memory rather than for cognition as a whole.^{[1], [2]}

Strength and limits of the evidence

The available evidence comes from a relatively small number of randomized controlled trials with modest participant numbers, low-to-moderate risk of bias, and substantial statistical heterogeneity. The certainty of evidence was rated moderate for memory and low for other cognitive domains. Taken together, the data suggest a possible but limited effect of creatine on memory, with broader cognitive benefits remaining unconfirmed.^{[1], [2]}

Limitations of the current evidence

Conclusions rest on a small body of randomized trials with modest sample sizes and considerable variability between studies, so the small pooled memory effect should be interpreted cautiously and not generalized to all people or all cognitive functions.^{[1], [2]}

The apparently larger benefit in older adults is based on few trials with high heterogeneity, and there was no significant pooled effect on overall cognition or executive function; larger, more rigorous trials are needed before firm conclusions can be drawn about who benefits and at what dose.^{[1], [2]}