Creatine has the strongest evidence for a memory effect in older adults (66+), where multiple studies report a moderate to large effect, although variation between studies is high and study quality is inconsistent. In younger adults, the largest available RCT shows no convincing cognitive benefit. For anyone considering creatine purely for memory, the strongest case currently applies to older adults who also do strength training, and the weakest case applies to young, healthy adults.
Creatine increases the energy supply in brain cells, and several studies have investigated whether this also benefits cognitive performance. Across all age groups combined, a meta-analysis shows a statistically significant but small memory effect (SMD = 0.29), with considerable variation between individual studies1. In other words: there is a signal, but it is not large enough or consistent enough to rely on with confidence.
The most convincing effect has been found in older adults (66-76 years). The same meta-analysis reports a moderate to large effect on memory in that group (SMD = 0.88), and a small randomised study with 32 older adults found improvement on virtually all measured cognitive tasks after one week of creatine (5 grams, four times per day)2,1. A recent systematic review of people aged 55 and over (more than 1,500 participants) reached a similar conclusion: five of the six included studies reported positive outcomes for memory and attention3. The caveat is always the same: variation between studies is high, and the methodological quality of most of the underlying studies was moderate to poor. The signals are therefore promising, but have not yet been confirmed by large-scale, high-quality research.
In younger adults the picture is clearly less positive. The largest randomised trial conducted to date in this area (123 participants, including an equal distribution of vegetarians and meat-eaters) found no statistically convincing cognitive benefit for reasoning or working memory after six weeks of creatine at 5 grams per day4. Meta-analysis data confirm that in people aged 11 to 31 the average effect on memory and cognition is close to zero (SMD = 0.03,1,5. For attention, reaction time and executive functions, results across the literature are contradictory5.
Side effects deserve separate attention. In the large RCT among young adults, complaints, particularly gastrointestinal complaints, occurred significantly more often in the creatine group than in the placebo group (relative risk 4.25,4. That is not a reason to label creatine as dangerous, but it is a relevant consideration if you are thinking of taking it purely for cognitive benefits in an age group that is unlikely to gain much from it.
There are two situations in which creatine appears particularly interesting for older adults. First, the combination with strength training: a narrative review describes that exercise appears to amplify the cognitive effect of creatine6. Second, metabolic stress such as sleep deprivation: there are indications that creatine replenishes brain stores precisely when the brain is under greater strain, but this has barely been studied in controlled trials7. For vegetarians, who naturally take in less creatine through diet, a larger benefit seemed conceivable, but the largest RCT found no statistically significant difference between vegetarians and meat-eaters4,8,5.
Based on two meta-analyses/systematic reviews (PMID 35984306, 40971619), multiple randomised studies including the largest RCT in this field (PMID 37968687, n=123), and additional smaller RCTs and narrative reviews. Total estimated number of participants across all sources: approximately 2,200+. The methodological quality of the underlying studies varies considerably.