Supplements · Evidence

Creatine Explained: The One Supplement Worth Taking

Creatine monohydrate is the most studied, most effective and cheapest supplement in fitness. Here is what it actually does, exactly how to take it, and why the safety scares are myths.

MB By Mustafa Bilgic · Updated 2026-06-13 · 9 min read · Supplements

Key takeaways

Creatine is the most researched and most effective sports supplement — and one of the cheapest.
It helps muscles regenerate energy (ATP) for short, intense efforts — a few more reps over time.
Take 3–5 g of monohydrate daily; loading is optional, timing barely matters.
It is safe for healthy people and does not harm the kidneys at normal doses.
Any early weight gain is water in the muscle, not fat.

If you took every supplement in a typical store and ranked them by how much evidence supports them, one would tower above the rest: creatine monohydrate. It is the most studied sports supplement in existence, with hundreds of trials behind it, and it is also one of the cheapest. Yet it remains wrapped in myths about kidneys, water weight and loading phases. Let us cut through them.

What creatine actually does

Your muscles run on a molecule called ATP for short, explosive efforts. ATP gets used up within seconds, and creatine helps regenerate it — effectively expanding your tank for high-intensity work. In practice, that means you can squeeze out an extra rep or two, lift slightly heavier, and perform better in repeated hard bouts. Those small improvements, applied over months of progressive training, add up to greater gains in strength and muscle. It is not a steroid or a stimulant; it simply lets you train a little harder.

How to take creatine

It could hardly be simpler:

Form: plain creatine monohydrate. Skip the fancier (and pricier) versions — they are not better.
Dose: 3–5 g per day, every day.
Timing: whenever you will remember — with a meal or post-workout is fine, but timing has only a minor effect.
Consistency: this is the key. Creatine works by saturating your muscles over time, so daily intake matters far more than when you take it.

Should you load creatine?

Loading — taking around 20 g/day (split into 4 doses) for 5–7 days — saturates your muscles faster, within about a week. But it is entirely optional. Simply taking 3–5 g daily reaches the same full saturation in about three to four weeks, with less chance of the mild stomach upset that high loading doses can cause. Both routes end in the same place; loading just gets there sooner.

Loading (steeper line) reaches full muscle saturation in about a week; a steady 3–5 g/day gets there in 3–4 weeks. The end point is identical.

The safety and water-weight myths

Two persistent myths deserve burial:

“Creatine damages your kidneys.” For healthy people, decades of research show creatine monohydrate is safe at recommended doses and does not harm kidney or liver function. The myth largely stems from creatine raising creatinine, a lab marker — a harmless side effect of supplementation, not a sign of damage. Those with existing kidney disease or who are pregnant should still check with a doctor.
“Creatine makes you fat / bloated.” Any quick scale increase — usually 1–2 kg — is water drawn into the muscle cells, which actually makes muscles look fuller. It is not fat and it is not subcutaneous bloat. It stabilises after a couple of weeks.

A sensible caveat

Creatine is remarkably safe for healthy adults, but no supplement is right for everyone. If you have a kidney condition, are pregnant or breastfeeding, or take medication, talk to your doctor before starting — standard advice for any supplement.

Who benefits from creatine?

Most people who do resistance training or repeated high-intensity work — lifters, sprinters, team-sport athletes. A minority are “non-responders” whose muscles are already creatine-rich from diet, but most see a benefit. It pairs naturally with adequate protein and good sleep as one of the few supplements genuinely worth the money. If you are weighing other products, see our evidence-based breakdown in pre-workout explained.

Sources & further reading

External links are provided for reference and do not imply endorsement. arsenal.fit is an independent publisher and is not affiliated with any cited organisation.

Not medical advice. arsenal.fit publishes general educational fitness information. It is not a substitute for professional medical guidance. Talk to a doctor before starting a new exercise programme, especially if you are pregnant, recovering from injury or illness, or managing a health condition. Sources are cited from public health and exercise-science organisations (CDC, ACE, NSCA, ACSM, PubMed).

Frequently asked questions

What does creatine actually do?

Creatine helps your muscles rapidly regenerate ATP, the energy currency for short, intense efforts. In practice that means a few more reps, slightly heavier sets, and better performance in repeated bouts of hard work — which, over time, supports greater strength and muscle gains. It is the most consistently effective ergogenic supplement studied.

Do I need to load creatine?

No, loading is optional. A loading phase (around 20 g/day for 5–7 days) saturates your muscles faster, but simply taking 3–5 g daily reaches the same saturation in about three to four weeks with less risk of stomach upset. Both end up in the same place; loading just gets there sooner.

Is creatine safe?

For healthy people, creatine monohydrate has an excellent safety record across decades of research and is considered safe at recommended doses. It does not damage the kidneys or liver in healthy individuals. As with any supplement, those with pre-existing kidney conditions or who are pregnant should consult a doctor first.

Does creatine make you gain weight?

It can cause a small, fast increase in scale weight — typically 1–2 kg — but this is water drawn into the muscle cells, not fat. Many people see this as a positive (fuller-looking muscles). It is not bloating or fat gain, and it stabilises after the first couple of weeks.

Which type of creatine is best?

Plain creatine monohydrate. It is the most researched, the most effective, and by far the cheapest. Fancier forms (HCl, buffered, etc.) are marketed as superior but have not been shown to outperform monohydrate. Save your money and buy monohydrate.

When should I take creatine?

Timing has only a minor effect — consistency matters far more, because creatine works by saturating your muscles over time. Take your 3–5 g at whatever time you will remember every day. Taking it with a meal or post-workout is fine but not essential.