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Creatine: The Supplement That Earns Its Place

Nutrition2 min readKreider et al., JISSN (2017)

Creatine adds a little extra strength and muscle on top of training, costs little, and has a strong safety record. It works by building up, so daily beats timing.

Key points
  • Taken alongside resistance training, it adds a little more strength and lean mass than training alone.
  • 3 to 5g a day fills your muscles in about four weeks; a 20g-a-day loading week gets there faster.
  • Expect a kilogram or two early on: water drawn into muscle, not fat.
  • It has a strong safety record in healthy people. With kidney disease, ask your doctor first.

What it does

Creatine tops up your muscles' store of phosphocreatine, the fuel for short, all-out efforts like a heavy set or a sprint. It is one of the most studied supplements there is, and across many trials, taking it alongside resistance training adds a little more strength and lean mass than the same training without it. Not a lot, but real, and for pennies a day.

How to take it

About 3 to 5g a day fills your muscles in roughly four weeks. A loading phase of about 20g a day, split into four doses, for five to seven days gets there in under a week, and a small daily dose keeps it there. Because it works by building up, taking it every day matters far more than when in the day you take it.

What to expect

Most people gain a kilogram or two in the first week of loading, mostly water drawn into the muscle, not fat, so do not read it as a failed week on the scale. In healthy people it has a strong safety record, including in studies lasting years. If you have kidney disease, check with your doctor before you start.

See a GP if…
  • You have kidney disease or reduced kidney function, before you start taking it
  • You're due a kidney blood test: tell the clinician you take creatine, as it can raise the result
How Kriterion uses this

Logging creatine in Kriterion is free. With Premium, the maintenance estimate sets aside the water from a loading phase instead of reading it as fat, and the Supplement Consistency card counts how many days of the last fortnight hit the dose.

References

  1. Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition, 2017;14:18.
  2. Hultman E, Söderlund K, Timmons JA, Cederblad G, Greenhaff PL. Muscle creatine loading in men. Journal of Applied Physiology, 1996;81(1):232-237.
  3. Branch JD. Effect of creatine supplementation on body composition and performance: a meta-analysis. International Journal of Sport Nutrition and Exercise Metabolism, 2003;13(2):198-226.

Last reviewed 28 Sep 2026 · Next review due Sep 2029

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