The most researched, most reliable, and cheapest performance supplement there is — and most people take it wrong.
Creatine is the rare supplement where the science is genuinely settled. Hundreds of studies over several decades show it reliably improves strength, power, and the amount of work you can do in the gym, with a safety record that is about as clean as any supplement gets. It is also one of the cheapest things you can buy, which is exactly why the industry spends so little marketing it and so much marketing everything else.
This guide covers what creatine actually does, the only form worth buying, how to dose it without wasting money on a 'loading phase' you probably do not need, and the handful of real considerations around water weight and stomach comfort. The short version: buy plain creatine monohydrate, take 5 grams every day, and skip the fancy versions.
What it is
Creatine is a compound your body already makes and stores mostly in muscle, where it helps rapidly regenerate ATP — the fuel your muscles use for short, hard efforts like a heavy set or a sprint. Supplementing raises the amount of creatine stored in your muscles, which lets you squeeze out slightly more reps, a bit more power, and better performance on repeated intense efforts.
You also get creatine from meat and fish, but the amounts are small, so a daily supplement is the practical way to top up your stores. Creatine monohydrate is the specific form that virtually all the research is built on; the newer 'HCL', 'buffered', or 'liquid' versions are more expensive and have no evidence of being better.
What the evidence supports
- Consistent, well-replicated improvements in strength and power output across a huge body of research.
- More total training volume over time, which is one of the main drivers of muscle growth.
- Better performance on short, repeated high-intensity efforts — exactly the kind of work HIIT is built on.
- Growing evidence for cognitive benefits, especially under sleep deprivation or mental fatigue.
- Extremely cheap per serving and safe for long-term daily use in healthy people.
How to use it
Dose: 5 g of creatine monohydrate per day, every day. A 'loading phase' (about 20 g/day split into 4 doses for 5-7 days) fills your stores faster but is optional — plain 5 g daily reaches the same level in a few weeks.
Timing: Timing barely matters because it works by saturating your muscles over time. Take it whenever you'll remember — many people add it to a daily shake or their post-workout drink.
Take it consistently, including on rest days. Drink normal amounts of water. The 1-3 lb of scale weight some people see early is water pulled into muscle, not fat. This is general guidance, not medical advice; if you have kidney disease or are pregnant, check with your doctor first.
What to look for
- Buy plain creatine monohydrate — ideally labelled 'Creapure', a widely used tested source — and ignore HCL, buffered, or liquid forms.
- Look for a single-ingredient product with no proprietary blends, sweetener stacks, or added stimulants.
- Micronized monohydrate mixes a little better but is otherwise identical; don't pay a big premium for it.
- Choose a third-party tested brand (NSF Certified for Sport or Informed Sport) if you are a tested athlete.
FAQ
Do I have to do a loading phase?
No. Loading just fills your muscle stores in about a week instead of a few weeks. If you're not in a rush, plain 5 g per day gets you to the exact same place with less stomach upset and less waste.
Will creatine make me bloated or 'puffy'?
Creatine draws a little water into the muscle itself, which can add 1-3 lb on the scale early on. It does not cause the under-the-skin bloat people worry about, and the effect settles quickly.
Is creatine safe for my kidneys?
In healthy people, long-term studies show no harm to kidney function. It can slightly raise a blood marker (creatinine) that looks like a kidney flag on a lab test, so tell your doctor you take it. If you have existing kidney disease, ask your doctor first.