Creatine and the Brain: What the Memory, Mood and ADHD Trials Found

Oral creatine raises brain creatine by about 5 to 10%, a fraction of the rise in muscle. Pooled trials show a small memory effect, largest over 65 and near zero under 31, and the UK refused a cognition claim in 2024. The depression trials are small add-ons to treatment, and no trial exists in ADHD or anxiety. What creatine does covers the muscle evidence.

What does creatine do in the brain?

The brain holds creatine as phosphocreatine and takes it up slowly. In six volunteers, 20 g (grams) a day for four weeks raised brain creatine 8.7%, a change that had reversed three months later.¹ In 64 people on 0.3 g per kilogram a day for seven days, brain phosphocreatine did not change while muscle phosphocreatine rose 10 to 28%.² A 2025 review, whose authors declare industry ties, put the brain rise at 5 to 10% against 20 to 40% in muscle; the dose and time relationship "remains to be determined".³

Memory, focus and brain fog: what the trials found

"Brain fog" is the reader's word, not a trial outcome: no creatine trial has measured it. A 2023 meta-analysis of eight trials found memory scores higher on creatine than placebo (standardised mean difference 0.29): 0.88 in adults aged 66 to 76, with 83% heterogeneity, and 0.03 at ages 11 to 31.⁴ A published letter argued that the analysis double-counted participants.⁵ A 2024 meta-analysis of 16 trials found a memory difference of 0.31 at moderate certainty, attention and processing-speed differences at low certainty, and nothing on overall cognition.⁶ The largest single trial, 123 adults on 5 g a day for six weeks, was borderline (p = 0.064 on one memory test).⁷ See creatine in perimenopause and menopause and is omega-3 good for your brain.

In an opinion published on 14 August 2024, the UK Nutrition and Health Claims Committee assessed a proposed cognition claim at up to 3 g a day. One of ten submitted trials was pertinent, 22 adults on 2.2 g a day for six weeks, and it "reported no difference between creatine supplementation and placebo groups for any cognitive outcome"; the committee concluded that "a cause-and-effect relationship has not been established", so the claim is non-authorised in Great Britain.⁸ A finding about dose and age, not a verdict on creatine.

Sleep loss and mental tiredness

In two small trials, the first of 19 adults, 20 g a day for seven days before a night without sleep meant less decline on movement, reaction-time, balance and mood tests at 24 hours awake and a better score on one executive task at 36 hours; nothing else differed.^{9, 10} In 29 adults awake for 21 hours, a single dose of 0.2 g per kilogram (about 14 g for a 70 kg adult, our estimate) gave up to 12% less deterioration on logic, numerical and language tasks.¹¹ Creatine is not a stimulant, and the 2025 review found no evidence of a cognitive effect in people who have slept normally.³

Can creatine affect your sleep or dreams?

Sleep quality has never been a creatine trial outcome. Broken sleep and vivid, disturbing dreams are the most common negative experience in the forum threads read for this page, "really broken sleep and incredibly disturbing dreams" among them. The one trial that measured salivary melatonin found no group difference, in people awake for 36 hours.¹⁰ If your sleep worsens, take the dose earlier in the day; creatine is not caffeine, as when to take creatine explains, and caffeine and sleep covers coffee.

Can creatine cause anxiety, anger or low mood?

No trial has recorded irritability, anger or anxiety as an outcome in healthy adults; in the sleep-deprivation trials cortisol and catecholamines did not differ between creatine and placebo.^{9, 10} The reports exist, "so mean and irritated I couldn't be around people" among them; they are reports, not rates. The one safety finding is from the bipolar depression trial below: two of 17 people on creatine switched to hypomania or mania.¹² If your mood changes after starting anything new, stop and tell your GP; creatine side effects covers the physical ones.

What trials show for depression

All the randomised trials were add-ons to treatment under psychiatric care. In the one positive trial, 52 women starting escitalopram took 5 g a day or placebo for eight weeks, and depression scores fell more on creatine.¹³ In 18 people not responding to an antidepressant, 5 or 10 g a day for four weeks made no difference from placebo.¹⁴ In 35 people with bipolar depression, 6 g a day for six weeks did not change the main depression score; remission, a secondary measure, was 52.9% against 11.1%, and two people on creatine switched to hypomania or mania.¹² A 2025 meta-analysis of 11 trials and 1,093 participants put the pooled difference at 2.2 points on the 17-item Hamilton scale, below the 3.0-point minimal important difference, at very low certainty.¹⁵

Never stop or change a prescribed medicine because of any of this, and talk to your GP. The NHS says "you can refer yourself to NHS talking therapies without speaking to a GP" if you are registered with one and aged 18 or over (16 in some areas).¹⁶

Is creatine good for ADHD or anxiety?

No trial has tested creatine in ADHD or in anxiety. A PubMed search in October 2026 found no ADHD trial, and a 2026 systematic review of randomised trials in mental disorders (five trials, 238 people) wrote: "No other mental disorders were investigated".¹⁷ In July 2025 and April 2026 the Advertising Standards Authority upheld complaints about anxiety, stress, ADHD and depression wording on a children's supplement and a functional drink, treating it as disease claims. The NHS: "ADHD medicines must be started and monitored by an ADHD specialist".¹⁸ Does lion's mane help with ADHD shows the same no-trial pattern; under-18s belong on is creatine safe for teenagers.

How much creatine do brain studies use, and for how long?

No trial has established a dose for the brain; this page gives none. The studies above used 20 g a day for weeks, 5 g a day for six to 24 weeks, a single dose of about 14 g under sleep loss, and 2.2 g a day for six weeks.^{1, 7, 8, 9, 11, 19} The one trial at 3 g a day or less found no difference from placebo, and no trial has timed an effect. The one wording authorised in Great Britain is about muscle: "Creatine increases physical performance in successive bursts of short-term, high intensity exercise", obtained with a daily intake of 3 g, for adults performing high-intensity exercise (how much creatine should you take).²⁰ Drink as you normally would; the NHS guide is 6 to 8 cups or glasses of fluid a day, more in heat or during long sessions.²¹

Concussion: one open-label trial gave 39 injured children and adolescents 0.4 g per kilogram a day for six months and reported shorter post-traumatic amnesia and intensive-care stays; nobody was blinded, and three controlled trials were under way at the 2025 review.^{22, 3} Creatine is not a protection. After a head injury the NHS says to call 999 if someone has been knocked out and not woken up, cannot stay awake or has a fit, and 111 for vomiting, dizziness or any other worrying symptom.²³

Frequently asked questions

Can taking creatine cause brain fog?

No trial has recorded it. In the largest trial, 123 adults on 5 g a day, side effects were reported about four times as often as on placebo; a foggy head was not a measured outcome.⁷

Is creatine good for brain health?

Brain creatine rises 5 to 10% at high doses; pooled memory differences are small and concentrated over 65; the UK refused a cognition claim at 3 g a day in 2024.^{3, 4, 7, 8}

Can creatine help with dementia?

No controlled trial exists in dementia. A 2026 scoping review found one pilot of 20 people on 20 g a day for eight weeks; the 24-week trial in 56 older women changed no cognitive measure.^{19, 24}

Do vegetarians get more from creatine for the brain?

In 45 vegetarians, 5 g a day for six weeks raised working-memory and reasoning scores; in 128 women on 20 g a day for five days, memory was better in vegetarians only; in the 123-adult trial, "Vegetarians did not benefit more from creatine than omnivores".^{7, 25, 26} What foods contain creatine explains why plant-based diets start lower.

Does creatine interact with antidepressants?

No interaction study exists. The add-on trials gave creatine alongside escitalopram and other antidepressants, with adverse events no more frequent than on placebo.^{13, 14} Tell whoever prescribes your medicine before adding anything.

Sources

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4. Prokopidis K, et al. Effects of creatine supplementation on memory in healthy individuals: a systematic review and meta-analysis of randomized controlled trials. Nutrition Reviews, 2023. PubMed 35984306.
5. Eckert I, Pascher E. Letter to the Editor. Nutrition Reviews, 2023. PubMed 36644917.
6. Xu C, et al. The effects of creatine supplementation on cognitive function in adults: a systematic review and meta-analysis. Frontiers in Nutrition, 2024. PubMed 39070254.
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15. Eckert I, Lima J, Dariva AA. British Journal of Nutrition, 2025. PubMed 41189312.
16. NHS. NHS talking therapies, last reviewed 5 November 2025; fetched 11 October 2026. nhs.uk.
17. Jeryous Fares B, et al. Canadian Journal of Psychiatry, 2026. PubMed 41558805.
18. NHS. ADHD: treatment, last reviewed 19 March 2025; fetched 11 October 2026. nhs.uk.
19. Alves CR, et al. PLoS One, 2013. PubMed 24098469.
20. DHSC. Great Britain nutrition and health claims register, last updated 19 May 2026; fetched 11 October 2026. gov.uk.
21. NHS. Water, drinks and hydration, last reviewed 17 May 2023; fetched 11 October 2026. nhs.uk.
22. Sakellaris G, et al. Journal of Trauma, 2006. PubMed 16917445.
23. NHS. Head injury and concussion, last reviewed 29 May 2025; fetched 11 October 2026. nhs.uk.
24. Whitford T, et al. Ageing Research Reviews, 2026. PubMed 42668123.
25. Rae C, et al. Proceedings of the Royal Society B, 2003. PubMed 14561278.
26. Benton D, Donohoe R. British Journal of Nutrition, 2011. PubMed 21118604.

This article is general information, not medical advice. No brain, memory, mood or cognition claim is authorised for creatine in Great Britain.