What are the side effects of Creatine Monohydrate?

Minor water weight or initial GI upset Loose stools if taken as one large dose A benign rise in serum creatinine (a lab marker, not kidney damage)

Who should avoid Creatine Monohydrate?

Pre-existing kidney disease without clinician oversight Pregnant or breastfeeding without clinician guidance

Amino acid

Creatine Monohydrate

Best known for muscle, creatine is also a brain energy-buffer. Its cognition evidence is modest and contested: the positive signals come from high acute doses during sleep deprivation and from older adults, while the largest trial in rested adults was borderline and EFSA's 2024 review found no established cognitive effect. Extremely cheap with a strong safety record.

Grade CUpdated September 17, 2026Written and fact-checked in-house against The Evidence Standard. Not a clinical review.

Please note

Educational content, not medical advice. Doses below are ranges used in research, not recommendations. Talk to a qualified clinician before starting any supplement, especially if you take medication, are pregnant, or manage a health condition.

Evidence grade: Evidence: Grade C
Studied dose range: 3–5 g/day maintenance in most trials. The sleep-deprivation studies used one-off doses of about 0.2–0.35 g/kg (roughly 14–25 g for a 70 kg adult), a research context, not a daily-use recommendation.
Time to effect: Days to ~2–4 weeks to saturate brain and muscle stores at 3–5 g/day; no reliable acute everyday effect.
Best form: Creatine monohydrate (Creapure-grade is a common quality marker). Other forms carry no proven advantage.

On this page

Full profile
Evidence
Side effects
Who should check first
Interactions
Stacking
Label guidance
References
Revision history

The short answer

Creatine Monohydrate (Amino acid) is studied for cognitive resilience under acute sleep loss (studied at research doses) and older adults curious about memory support (tentative signal). In our conservative reading of the published human research, the evidence is Grade C (limited). 3–5 g/day maintenance in most trials. The sleep-deprivation studies used one-off doses of about 0.2–0.35 g/kg (roughly 14–25 g for a 70 kg adult), a research context, not a daily-use recommendation. Days to ~2–4 weeks to saturate brain and muscle stores at 3–5 g/day; no reliable acute everyday effect. A studied dose is what trials used, not a recommended dose.

Full profile

Also known as	Creatine, Creapure (branded)
Best for	Cognitive resilience under acute sleep loss (studied at research doses) · Older adults curious about memory support (tentative signal) · Stimulant-free brain-energy support
Evidence grade	Grade C · Limited: early or small human trials
Studied dose range	3–5 g/day maintenance in most trials. The sleep-deprivation studies used one-off doses of about 0.2–0.35 g/kg (roughly 14–25 g for a 70 kg adult), a research context, not a daily-use recommendation.
Time to effect	Days to ~2–4 weeks to saturate brain and muscle stores at 3–5 g/day; no reliable acute everyday effect.
Best form	Creatine monohydrate (Creapure-grade is a common quality marker). Other forms carry no proven advantage.
Food sources	Red meat, Herring and salmon, Poultry (lower amounts)

Evidence, honestly graded

Held at C on 2026-09-14, and a proposed upgrade was rejected. EFSA's 2024 review of a creatine cognition claim found no cause-and-effect relationship in any cognitive domain at 3 g/day: working-memory effects appeared only at 20 g/day for 5–7 days, not with 5 g/day for six weeks, and the applicant's meta-analysis counted the same participants more than once. When a widely cited 2023 memory meta-analysis was re-analysed without that double counting, the overall benefit was no longer significant except in adults aged roughly 66–76 (Eckert & Pascher 2023). The largest trial in healthy adults (Sandkühler 2023, n=123, 5 g/day for six weeks) found only a borderline effect on backward digit span, and vegetarians did not benefit more. An earlier systematic review (Avgerinos 2018) had suggested memory gains concentrated in stressed or older groups. Single doses of about 0.2–0.35 g/kg improved performance during sleep deprivation in two small studies from one research group (Gordji-Nejad 2024 and 2026). These were acute research doses, not a daily-use effect. Reviewed 2026-09-17: a 2026 trial in young active adults found creatine improved Wingate cycling performance but not cognition (Silva et al.), and a 2026 scoping review looking for creatine trials in dementia found no randomized controlled trials at all. Honestly C.

See the full grading rubric (study type, replication, population match, and dose adequacy) in The Evidence Standard.

71 natural health products with an active licence in Health Canada's LNHPD list Creatine Monohydrate as a medicinal ingredient.

That makes Creatine Monohydrate a recognized, licensable medicinal ingredient in Canada, regulated by Health Canada's Natural and Non-prescription Health Products Directorate, which issues each licensed natural health product a Natural Product Number (NPN). Search the LNHPD to verify.

Source: Health Canada Licensed Natural Health Products Database, snapshot 2026-09-28. A count of products with an active licence, not an endorsement of any health claim. This describes the ingredient's regulatory standing in Canada, not Signal State Core, which is a pre-launch concept and is not a licensed natural health product.

Side effects

Minor water weight or initial GI upset
Loose stools if taken as one large dose
A benign rise in serum creatinine (a lab marker, not kidney damage)

Who should avoid it or check first

Pre-existing kidney disease without clinician oversight
Pregnant or breastfeeding without clinician guidance

Interactions

Can elevate measured serum creatinine; tell your clinician you supplement so kidney function is not misread
Use caution with nephrotoxic drugs; discuss with a clinician

Stacks well with

What to look for on a label

State creatine monohydrate in grams and note that a benign serum-creatinine rise is expected and is not kidney harm.
Health Canada's Creatine monograph is built around exercise/muscle/strength performance. There is no monograph cognition claim, so a brain/focus claim cannot ride the creatine monograph and would need its own evidence.

References

Silva 2026, Research in Sports Medicine: performance yes, cognition no. Creatine monohydrate improved cycling Wingate performance but not cognitive function in young active males and females, a useful separation of the two claims. PMID 41960895; doi:10.1080/15438627.2026.2656695. Educational, not a product claim.
Whitford 2026, Ageing Research Reviews: scoping review. Searched 8,317 records for creatine and dementia-related cognitive outcomes and found no randomized controlled trials; the human evidence was one 20-person pilot. PMID 42668123; doi:10.1016/j.arr.2026.103317.
Avgerinos 2018, Exp Gerontol: systematic review. Modest memory/reasoning signal, strongest in stressed or low-baseline groups. PMID 29704637; doi:10.1016/j.exger.2018.04.013. Educational, not a product claim.
Gordji-Nejad 2024, Scientific Reports: sleep-deprivation crossover. Single high dose improved cognition and brain phosphocreatine during 21-hour sleep loss (n=15). doi:10.1038/s41598-024-54249-9. Educational.
Kreider 2017, J Int Soc Sports Nutr: ISSN safety position. Long-term safety review; no evidence of kidney harm in healthy people, plus the creatinine-marker caveat. PMID 28615996; doi:10.1186/s12970-017-0173-z.
EFSA NDA Panel (2024): creatine and improvement in cognitive function. Scientific opinion on a proposed EU health claim at 3 g/day: no cause-and-effect relationship established for any cognitive domain; the submitted meta-analysis double-counted participants. PMID 39564533; doi:10.2903/j.efsa.2024.9100. The main independent basis for holding the grade at C.
Eckert & Pascher 2023, Nutrition Reviews: re-analysis letter. Showed that a 2023 creatine-and-memory meta-analysis treated multiple outcomes from the same participants as independent; corrected, the overall memory effect was no longer significant except in older adults. PMID 36644917; doi:10.1093/nutrit/nuac108.
Sandkühler JF, Kersting X, Faust A, et al. (2023). BMC Medicine, 21(1):440Randomized, double-blind, placebo-controlled crossover, n=123, 6 weeks per conditionStudied dose: 5 g dailyBorderline effect on backward digit span (p = 0.064) and none on Raven's matrices (p = 0.327); vegetarians did not benefit more; more side effects than placebo.
Gordji-Nejad 2026, Nutrients: single-dose creatine during sleep deprivation. Follow-up from the same research group (n=29, 0.2 g/kg): mitigated sleep-loss declines on some tasks, with smaller effects than the 2024 study. PMID 42075005.

Grades and studied doses are our conservative reading of the human research, shown for education. They are not product claims, and a studied dose is not a recommended dose.

Revision history

Every change to this ingredient's evidence status, dated and explained. The full cross-library log lives at Evidence Updates.

2026-09-17Citation review
Added two 2026 sources that separate the performance claim from the cognitive one: a trial in young active adults where creatine improved Wingate cycling performance but not cognition, and a scoping review that searched 8,317 records for creatine trials in dementia and found no randomized controlled trials at all. C holds.
2026-09-14Citation review
Reviewed for an upgrade and held at C. EFSA's 2024 opinion found no established cognitive effect, a corrected re-analysis of the main memory meta-analysis was not significant outside older adults, and the largest healthy-adult trial was borderline.
2026-07-05New profile
Initial profile published at Grade C: a 6-RCT systematic review suggests short-term memory and reasoning gains concentrated in stressed or low-baseline states.

See how Creatine Monohydrate compares on grade, dose, and goal in the Evidence Explorer.

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