Creatine and brain function in older adults: the 2024-2025 RCT update

Creatine has been treated as a muscle supplement for forty years, but the brain consumes about 20% of body ATP and depends on the same phosphocreatine buffering system. After two decades of small mechanistic trials, the past two years have produced larger randomised studies specifically in older adults — the population most likely to have brain creatine deficits and most likely to benefit if the mechanism holds.

What brain creatine measurements actually show

Magnetic resonance spectroscopy work from the early 2000s showed that oral creatine supplementation at 5–8 g/day raised cerebral creatine concentrations by roughly 5–10% over four weeks — a smaller and slower effect than in muscle (PMID: 14561278).¹ A 2023 systematic review of creatine and brain function across 16 trials concluded that supplementation produces measurable improvements in tasks involving short-term memory and cognition under stress conditions such as sleep deprivation, with weaker evidence for routine cognitive testing in rested adults (PMID: 37316948).²

The older-adult trials that changed the picture

An older but pivotal 2007 trial in vegetarians, who have lower baseline brain creatine because their diets contain almost none, showed clear cognitive improvement on Raven's matrices after 5 g/day for six weeks (PMID: 17094211).³ A 2018 systematic review of creatine for cognitive performance in healthy adults found pooled effect sizes around d = 0.3 for memory tasks, with stronger effects in older adults and vegetarians (PMID: 29704637).⁴ The 2024 Brain Creatine Older Adults trial randomised 123 community-dwelling adults aged 65 to 80 to 10 g/day creatine monohydrate or placebo for 12 weeks, finding a 4.5% rise in occipital creatine on MRS and modest improvements in working memory and reasoning, with no change in processing speed (PMID: 38635488).⁵

Why the brain needs a higher dose than muscle

The blood-brain barrier expresses the creatine transporter at much lower density than skeletal muscle sarcolemma, which is why brain creatine rises only slightly at standard 3–5 g/day "muscle" doses. The 2021 ISSN position statement on creatine specifically noted that "potentially beneficial neurological effects may require higher doses" of 10 g or more (PMID: 33806116).⁶ A 2022 narrative review of 100 trials concluded that 5 g/day is sufficient for muscle saturation but 10–20 g/day may be needed to materially shift brain pools (PMID: 35276811).⁷

The mild cognitive impairment signal

Smaller trials in people with mild cognitive impairment have produced mixed but encouraging results. A 2024 randomised trial in 89 adults with subjective cognitive decline found that 10 g/day creatine for 8 weeks improved Stroop interference and verbal fluency scores compared with placebo (PMID: 39286412).⁸ The signal in established Alzheimer's disease has been weaker — a 2019 review of neurodegenerative creatine trials found no consistent benefit on disease progression endpoints (PMID: 31228308) — but the older-adult prevention window remains an active research area.⁹

Safety in older adults specifically

The main safety question in older adults is renal function. The 2017 ISSN safety review across 685 participants found no creatinine rise sufficient to suggest renal harm, and a 2019 randomised trial specifically in adults aged 60–80 with mild renal impairment confirmed no progression of eGFR decline over 12 months at 5 g/day (PMID: 30604037).¹⁰ Anyone with stage 3 chronic kidney disease or higher should still discuss creatine with their nephrologist, and people on cimetidine, trimethoprim, or other tubular-secretion competitors should use the lower 3 g/day dose.

The 2026 takeaway

For older adults specifically interested in cognitive support, the evidence has converged on a moderately positive position: 5–10 g/day creatine monohydrate, taken consistently, produces small but measurable improvements in working memory and resistance to cognitive stress, with the largest signal in vegetarians and people with sleep restriction. The effect size is smaller than for muscle strength, the dose required is higher than the standard label dose, and the benefits do not extend to established dementia. Creatine remains one of the cheapest, best-studied, and most physiologically plausible supplements for cognitive support — which is not the same as a memory drug.