A note on this article: Creatine has been discontinued from the Proco range — the current lineup is Cognitive Support, Sleep Support, Sleep Formula, Omega-3 and Magnesium Glycinate. We're keeping the research below live because it's still accurate and useful — you just won't find Creatine in our shop.
Every creatine label eventually raises the same question: do you need to "load" — a short burst of high daily doses — or can you just start at a normal maintenance dose and let it build up on its own? The research on this is old, well-controlled, and genuinely clear. Here's what it actually shows, why the honest answer is "neither is wrong, they just get you to the same place on different timelines," and the parts of the picture that still aren't settled.
First, what "loading" is actually loading
On an ordinary omnivorous diet — which supplies roughly 1–2g of creatine a day from meat and fish — skeletal muscle sits at about 60–80% of its maximum creatine capacity. That headroom is the entire mechanism: supplementation works by filling the remaining 20–40%, raising muscle creatine and phosphocreatine content, not by adding something the muscle didn't already have. The 2017 International Society of Sports Nutrition (ISSN) position stand puts the achievable increase at 20–40% above baseline.2 It also means the people with the most room to gain are the ones who start lowest — vegetarians, low-meat eaters, and, as we cover in our piece on what the 2025 research adds on creatine and women, women, who average 30–40% lower dietary creatine intake than men.
The study that settled this
The definitive answer comes from a 1996 trial published in the Journal of Applied Physiology, which compared creatine protocols across 31 healthy men split into four groups.1 One group (n=6) took 20g/day, split into four 5g doses, for six days. A second (n=9) did the same six-day load then dropped to 2g/day for 28 days. A third (n=9) skipped loading entirely and simply took 3g/day from day one for 28 days. A fourth (n=7) ran a placebo-controlled urinary collection to track where the creatine went. Crucially, the researchers biopsied muscle tissue to directly measure intramuscular creatine content — not an indirect proxy, the actual stored amount in the muscle.
Both groups ended up with the same amount of creatine stored in muscle. One group just got there four times faster.
What the muscle biopsies actually showed
All groups started in the same place — muscle total creatine of roughly 119–124 mmol per kg of dry muscle, with no significant differences between them. Six days of 20g/day raised that by about 20%, to roughly 142–147 mmol/kg. The 3g/day group, taking a third of the daily dose with no loading phase at all, was up about 15 mmol/kg by day 14 and had accumulated roughly the same ~20 mmol/kg increase by day 28.1 Both approaches worked; the only difference the data supports is speed, not outcome.
The authors also noted something that gets left out of most summaries: between-subject variation in creatine uptake was, in their words, "rather large" — individual increases ranged from 2 to 40 mmol/kg. "Saturated" is an average, not a guarantee. Some people in that study barely moved. Nobody has a practical way to tell in advance which group you're in, which is a real limit on how precisely anyone can promise you a result.
~6 vs ~28 days
Time to reach saturated muscle creatine levels with a loading protocol (20g/day for 6 days) versus a maintenance-only protocol (3g/day from day one) — same end result, different timelines.
The scale weight is water, and the study proved it
The fourth arm of the Hultman trial explains the most misread side effect of loading. Creatine ingestion "markedly reduced urinary volume during the initial days" — by roughly 0.6 litres — which is what accounts for the 0.5–1.0kg of weight commonly gained during a loading week.1 It is retained fluid, not tissue. The 2021 ISSN review of common creatine misconceptions puts the typical loading-week increase at 1–3kg of body mass, "mostly attributable to net body water retention."3
Skipping the load largely sidesteps that. If a fast 1–3kg gain is a problem — a weight-class sport, a body-composition goal, or just not wanting to explain it — the 3–5g/day route reaches the same muscle content without the acute fluid shift. We go into where that water actually sits, and why it isn't dehydrating you, in does creatine actually dehydrate you and in our breakdown of bloating and water retention.
So is loading "necessary"?
No — not for the outcome itself. The 2021 ISSN review states it plainly: "accumulating evidence indicates that you do not have to 'load' creatine," and recommends roughly 3–5g/day for a minimum of four weeks to reach comparable saturation.3 Its practical framing is a decision rule rather than a rule: if you want the full effect inside 30 days, load; if you're taking it for longer than 30 days anyway, or want to avoid the fluid-related weight gain, don't.
Two dosing details are worth carrying over regardless of which route you take. First, single servings above roughly 10g are where gastrointestinal complaints — diarrhoea in particular — start showing up, which is why a 20g load is split into four 5g doses rather than taken in one go.3 Second, the ISSN position stand notes that co-ingesting creatine with carbohydrate, or carbohydrate and protein, has been reported to promote greater retention more consistently than taking it alone.2 That's a point in favour of taking it with a meal — which is also the simplest answer to whether you can take creatine on an empty stomach.
What happens when you stop
Loading is often framed as the start of a cycle, so it's worth knowing the back end. Once muscle stores are elevated, the position stand reports it generally takes 4–6 weeks for them to return to baseline, and no evidence suggests they fall below baseline afterwards — long-term suppression of the body's own creatine synthesis does not appear to occur.2 That's the evidence behind our broader view that there's no physiological case for cycling most supplements, and it also means a missed few days is not a reset. A week off does not send you back to day one.
Where the loading evidence stops
Three honest limits. First, Hultman's 31 participants were all men — the loading-versus-maintenance comparison has never been repeated at that level of methodological rigour in women, and muscle biopsy trials of this kind remain small by modern standards. Second, what was measured was muscle content, not performance: nobody has run a large head-to-head trial asking whether loading produces better strength or power outcomes than four weeks of 3–5g/day once both groups are saturated. The inference that equal saturation means equal results is reasonable, but it is an inference.
Third, muscle is not brain. The 2025 review of creatine in women's health notes that raising brain creatine appears to need higher intakes than muscle does — in the region of 15–20g/day for 5–7 days followed by 5–10g/day — and describes brain uptake as "still being explored."4 If your interest is cognitive rather than athletic, the muscle-saturation literature doesn't transfer cleanly; we cover that gap in how much creatine you need for cognitive benefits and in the wider look at what the cognitive research actually shows.
The practical takeaway
There's no version of this where skipping the loading phase means creatine "doesn't work" for you, and there's no version where loading is required to get the benefit. It's a timeline choice, not an efficacy choice: roughly a week with a load, roughly four weeks without, same endpoint, with a 1–3kg fluid gain and a higher chance of stomach complaints on the fast route. For most people taking it for months rather than weeks, the straightforward maintenance approach — 3–5g once a day, no loading protocol — is the simpler trade. If you want the deeper background, our complete guide to creatine monohydrate covers the wider evidence base, and creatine timing deals with the related question of when in the day to take it.
References
- Hultman E, Söderlund K, Timmons JA, Cederblad G, Greenhaff PL. "Muscle creatine loading in men." Journal of Applied Physiology, 1996;81(1):232–237. pubmed.ncbi.nlm.nih.gov
- Kreider RB, 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. tandfonline.com
- Antonio J, et al. "Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show?" Journal of the International Society of Sports Nutrition, 2021;18:13. pmc.ncbi.nlm.nih.gov
- Smith-Ryan AE, et al. "Creatine in women's health: bridging the gap from menstruation through pregnancy to menopause." Journal of the International Society of Sports Nutrition, 2025;22(1). pmc.ncbi.nlm.nih.gov
This article is for informational purposes only and has not been evaluated by the FDA. It is not intended to diagnose, treat, cure, or prevent any disease. Speak with a healthcare provider before starting any new supplement, especially if you take medication or have an existing health condition.
Related reading: Creatine Timing: Does Pre- vs Post-Workout Actually Matter?
Creatine is no longer part of the Proco range. If focus and cognitive performance is what you're after, Cognitive Support is the closest fit in our current lineup. Shop Cognitive Support →