Creatine supplements

Creatine and the brain: what about 20 g a day?

The 3–5 g a day every creatine product here is judged against is the dose for muscle and exercise. Studies on the brain have used more: 20 g a day, for 5–7 days or, in a small Alzheimer's pilot with no placebo group, for 8 weeks (Smith et al., 2025), or a single dose of 0.35 g per kg, about 26 g at 75 kg, during a night without sleep (Gordji-Nejad et al., 2024). The ISSN's creatine position stand notes that higher amounts over longer periods may be needed to raise creatine in the brain (Kreider et al., 2017).

The results are early and mixed. A 2023 meta-analysis found better memory mainly in older adults, not in younger ones (Prokopidis et al., 2023); a 2023 trial found no effect on cognition in young adults at moderate or high doses (Moriarty et al., 2023). In 2024 the EU's food safety authority, EFSA, saw an effect on working memory only at 20 g a day for 5–7 days, and concluded that a link between creatine and better cognition has not been established (EFSA, 2024). So we don't judge products against a brain dose.

Taking more? Split it

Studies that give 20 g a day split it: the usual loading plan is four doses of 5 g (Kreider et al., 2017), and the Alzheimer's pilot gave two doses of 10 g, with 13 mild side effects reported among its 20 patients, including diarrhoea, nausea and cramping (Smith et al., 2025). Large single doses are where stomach trouble shows up: in a trial with soccer players, diarrhoea was reported by 56% of those taking 10 g at once, against 29% of those taking the same 10 g as two doses of 5 g (Ostojic and Ahmetovic, 2008). Taken in normal amounts, creatine caused no more side effects than a placebo across 685 trials (Kreider et al., 2025).

Research context, not advice. If you have kidney disease or take medication, ask a doctor before taking high doses.