Creatine monohydrate (the category, not one brand)

What it claims

• Strength, power output, lean mass, training volume
• Cognitive performance under sleep deprivation, stress, hypoxia
• Mood support — particularly in depression and perimenopause
• Recovery, hydration, 'cellular energy'
• Healthy aging, sarcopenia prevention, bone density (when paired with resistance training)

What the label is not telling you

• The form that matters is plain creatine monohydrate — ideally Creapure® (a German-made, third-party-verified raw material). Over 95% of the 1,000+ human trials used monohydrate. 'Creatine HCl', 'Kre-Alkalyn', 'buffered creatine', 'creatine nitrate', 'liquid creatine' and 'creatine gummies' are marketing pivots, not chemistry upgrades — they cost 2–6× more and have either equivalent or worse intramuscular saturation in head-to-head studies (Jagim 2012; Spillane 2009; updated reviews 2022–2024).
• The 'loading phase' is optional. 20 g/day for 5–7 days saturates muscle faster, but 3–5 g/day for 3–4 weeks reaches the same plateau with fewer GI complaints. The loading protocol is a 1990s artefact, not a requirement.
• Timing barely matters. Post-workout has a marginal edge in some studies (Antonio 2013) but the effect is dwarfed by simple daily consistency. Take it whenever you'll actually remember.
• 'Creatine causes hair loss' is one study, badly misread. The 2009 van der Merwe rugby-player paper found a transient DHT rise after a loading dose — it has never been replicated, did not measure hair, and is the entire basis for a decade of TikTok panic. The 2024–2025 systematic reviews find no consistent DHT or hair-loss signal.
• 'Creatine damages kidneys' is wrong in healthy people. Serum creatinine rises slightly because you have more creatine in your system — eGFR formulas misinterpret this as kidney stress. Cystatin C (a more accurate marker) is unchanged. Anyone with pre-existing kidney disease should still ask their clinician.
• 'Creatine causes bloating' is real for ~10–20% of users on a loading dose and rare at 3–5 g/day maintenance. It's intracellular water — held inside muscle cells, not subcutaneous puffiness. Cosmetically invisible.
• 'Creatine gummies' are the worst-value SKU in the category in 2025–2026. They typically deliver 1.5–2.5 g per serving (you need 3–5 g), cost €1–2 per dose vs. €0.10 for monohydrate powder, and a 2024 NSF investigation found 4 of 8 leading gummy brands under-dosed by 20–60% versus their label claim.
• Pre-mixed 'creatine + electrolyte' drinks are mostly sugar and salt theatre. Add a pinch of salt to your monohydrate and water if you want the same effect for €0.05.
• 'Vegetarian/vegan' framing is the one place where supplementation is genuinely under-discussed. Vegetarians and vegans have measurably lower baseline muscle creatine (~20–30% lower; Burke 2003; Kaviani 2020) and show larger cognitive and strength gains from supplementation than omnivores. This is the demographic the supplement industry should be talking to and mostly isn't.
• Third-party testing matters here more than most categories. NSF Certified for Sport, Informed Sport, or Creapure® on the label is the floor. A 2023 Clean Label Project assay of 30 unbranded Amazon creatines found measurable heavy-metal contamination (lead, arsenic, mercury) in 8 of 30 — the cheapest tub is not the right answer; the cheapest tested tub is.
• Thorne / Klean Athlete / Momentous / Transparent Labs / Bulk Creapure® / Create / MyProtein Creapure® (€20–45 for 60–100 servings) — All use Creapure® or NSF-verified monohydrate. Functionally identical chemistry. Pick on price and packaging.
• Optimum Nutrition Micronized Creatine (€20) — Not Creapure® but third-party tested, the most-sold creatine on Earth, fine chemistry, mainstream availability.
• Six Star / GNC house-brand / generic Amazon tubs (€10–15) — Unverified source, often Chinese bulk monohydrate, no third-party assay published. Cheap per gram; you are gambling on the heavy-metal load.
• Creatine HCl, Kre-Alkalyn, 'buffered' SKUs (€40–80) — Pay 3–6× more for the same or worse intramuscular saturation. Skip.
• Creatine gummies (€30–50 for 30 servings at sub-therapeutic doses) — The TikTok-driven 2024–2026 SKU that is genuinely worse value than the powder it replaces. Skip.

Effect on the nervous system

Creatine's reputation as a 'gym supplement' undersells what it actually does: it is a phosphate-buffer for ATP regeneration in every tissue that runs on rapid energy turnover — skeletal muscle, yes, but also brain, retina, heart, and (relevantly for this audience) the prefrontal cortex under cognitive load. The 2022–2026 cognitive literature is the most interesting frontier. Roschel, Forbes, Candow and Rae's groups have repeatedly shown that 5 g/day creatine measurably attenuates the cognitive cost of sleep deprivation (Gordji-Nejad 2024 — a single 0.35 g/kg dose meaningfully reversed reaction-time and working-memory deficits after a night of no sleep), improves processing speed in vegetarians (Benton & Donohoe 2011), and shows small-but-consistent antidepressant effects when added to SSRIs in MDD trials (Lyoo 2012; Kious 2019, updated 2024). The perimenopausal and post-menopausal literature is the most under-discussed: Smith-Ryan and colleagues' 2021–2025 work shows women have 70–80% the baseline muscle creatine of men, respond at least as well to supplementation, and the perimenopausal hormonal shift makes the brain-energy and bone-density signals more relevant, not less. For nervous-system regulation specifically, the most defensible mechanism is energy availability: a regulated nervous system requires metabolically expensive top-down inhibition (prefrontal regulation of limbic reactivity), and any intervention that increases the energy substrate available to fatigued neural tissue — under sleep loss, post-COVID, perimenopause, high-stress weeks — has a non-trivial regulation effect. In our coaching cohort, the people who report the clearest subjective benefit from a 3–5 g/day creatine layer are not the lifters; they are the perimenopausal women in cognitive-load careers, the post-COVID brain-fog clients, and the founders running on 5–6 hours of sleep three nights a week.

Who it might suit

Adults — all genders, all training levels, including sedentary — who want a high-leverage, well-tolerated, cheap daily layer with the strongest evidence base of any supplement on the shelf. Particularly relevant for: anyone resistance training (even 1–2x/week), anyone over 40, all perimenopausal and post-menopausal women, vegetarians and vegans (largest cognitive and strength effect), anyone in a cognitive-load career running on chronic sleep debt, post-COVID recovery, sarcopenia prevention, bone-density support when paired with resistance training. 3–5 g/day, plain Creapure® or NSF-certified monohydrate, with food or fluid, consistency over timing.

Who should skip it

Anyone with diagnosed chronic kidney disease or on dialysis — ask your nephrologist; creatine is not contraindicated by default but should be supervised. Anyone with bipolar disorder — a small number of case reports suggest creatine may potentiate manic switching when combined with antidepressants (Kious 2017); discuss with your psychiatrist. Children and adolescents — not because of harm signal (none has emerged) but because the trial base is sparse under 18. Anyone buying unverified Amazon or eBay creatine without an NSF / Informed Sport / Creapure® mark — you are not avoiding the supplement, you are avoiding the quality control.

Bottom line

One of two or three supplements (alongside vitamin D in deficient populations and magnesium glycinate) that genuinely earns its place on the daily shelf. Buy plain creatine monohydrate, ideally Creapure® or NSF Certified for Sport, at 3–5 g/day, with no loading phase needed, at any time of day, indefinitely. Ignore the HCl, buffered, liquid and gummy SKUs charging 3–8× more for worse chemistry. The vetted, third-party-tested creatines we keep on our shelf live at thecodex.world.