Creatine monohydrate: benefits beyond the gym

By the DieticiansWorldwide.com editorial team · 17 October 2026 · Supplements & industry

What creatine is and what it actually does

Creatine is not a steroid or a stimulant. It is a compound your body makes and also gets from food. The liver and kidneys synthesise about 1 g a day from the amino acids glycine, arginine and methionine, and animal foods add more: beef and salmon each supply about 2 g per pound (454 g), and pork about 2.3 g, according to the NIH Office of Dietary Supplements (ODS, dietary supplements for exercise and athletic performance).

Around 95% of the body's creatine sits in skeletal muscle, with the rest mainly in the brain and testes. About two-thirds of muscle creatine is stored as phosphocreatine, which regenerates ATP, the cell's immediate energy currency, during the first seconds of hard effort. Each day about 1% to 2% of muscle creatine breaks down into creatinine, so the body has to replace roughly 1 to 3 g a day (International Society of Sports Nutrition position stand, 2017).

A supplement raises muscle stores above what diet alone provides. That extra phosphocreatine helps most in repeated short bursts, such as lifting, sprinting and jumping. ODS notes that creatine "seems to be of little value for endurance sports" such as distance running or swimming, and that the weight it adds may even hinder performance there.

So, what does creatine monohydrate actually do? It lets you do slightly more work in each hard set, and over weeks that extra training volume is what builds strength and muscle. It does not build muscle on its own while you sit still.

The evidence for muscle and strength

Creatine is one of the most studied supplements in sports nutrition. ODS summarises laboratory and field studies in which 5 to 7 days of supplementation improved strength, power and sprint performance in both men and women, and notes that the US Academy of Nutrition and Dietetics, Dietitians of Canada and the American College of Sports Medicine all advise that it improves performance in repeated high-intensity exercise with short recovery.

Responses vary. ODS points out that vegetarians, who start with lower muscle creatine, might respond more than meat eaters, and the ISSN position stand reports intramuscular stores in vegetarians of 90 to 110 mmol per kg of dry muscle, at the lower end of the usual range.

Creatine for older adults and healthy ageing

The biggest shift in the creatine conversation over the past decade has been away from young athletes and towards people in their 50s, 60s and beyond, who lose muscle and strength with age.

A 2017 meta-analysis pooled 22 randomised trials with 721 men and women, mean ages 57 to 70, who did resistance training two or three days a week for 7 to 52 weeks. Those taking creatine gained 1.37 kg more lean tissue than those on placebo (95% CI 0.97 to 1.76 kg), with modest extra gains in chest press and leg press strength (Chilibeck et al., Open Access Journal of Sports Medicine, 2017).

European regulators have accepted part of this evidence. Since 2017, products in Great Britain and the EU may state that "daily creatine consumption can enhance the effect of resistance training on muscle strength in adults over the age of 55." The conditions are strict: a daily intake of 3 g, alongside resistance training at least three times a week for several weeks, at 65% to 75% of the maximum load you can lift once, and the claim may only be used on foods aimed at adults over 55 who already train (Commission Implementing Regulation (EU) 2017/672, annex).

Notice what the claim does not say. It does not say creatine prevents frailty, falls or fractures, and it does not apply to people who do not train. The training is the treatment; creatine amplifies it.

Two cautions temper the excitement. First, "lean tissue mass" measured by scans includes water, and creatine draws water into muscle, so part of the 1.37 kg is fluid rather than new protein. Second, most trials are small and short, and few measured outcomes older people care about most, such as independence or falls.

Creatine for the brain: promising but not proven

Creatine for brain health is now one of the fastest-growing reasons people buy it. The ISSN position stand reports that supplementation can raise brain creatine content by about 5% to 15%, far less than in muscle.

The best summary of the human trials is a 2024 systematic review and meta-analysis of 16 randomised trials involving 492 adults aged 20.8 to 76.4 years, all using creatine monohydrate. It found a small positive effect on memory (standardised mean difference 0.31) and improvements in attention time and processing speed, but no significant improvement in overall cognitive function or executive function. The authors graded the certainty of evidence as moderate for memory and low for everything else. The benefit appeared larger in people with existing diseases and in women (Xu et al., Frontiers in Nutrition, 2024). The journal has since published a correction to the attention results, a reminder that a single review is not the last word.

The practical reading: creatine may give a small memory boost, particularly when sleep, stress or illness are taxing the brain, but it is not a treatment for dementia or cognitive decline, and no trial has shown that it prevents either. If you or a family member has new memory problems, see a doctor first.

How much to take, and whether loading matters

The ISSN position stand describes two routes to full muscle stores:

• Loading: 5 g four times a day (about 0.3 g per kg of body weight a day) for 5 to 7 days, then 3 to 5 g a day to maintain stores.
• No loading: 3 g a day, which raises muscle creatine gradually over about 28 days.

Both end in the same place. Loading gets you there in a week rather than a month, at the cost of more short-term water gain and a higher chance of stomach upset. For most people, especially older adults and anyone not preparing for a competition, a single daily dose of 3 to 5 g is simpler and matches the dose in the European health claim.

Timing matters far less than consistency. The European claim is worded around a daily intake, and the trials behind it gave creatine every day, so take it at whatever time of day you will remember rather than only before workouts.

The protein question: is creatine a substitute?

Creatine is not a source of protein, and it does not reduce your protein needs. This matters because protein advice is one of the most debated areas in nutrition right now.

The US Recommended Dietary Allowance for protein is 0.8 g per kg of body weight a day for healthy adults. ODS reports that more recent data suggest athletes need 1.2 to 2.0 g per kg. For people over 65, the European Geriatric Medicine Society's PROT-AGE study group recommends at least 1.0 to 1.2 g per kg a day, 1.2 g per kg or more for those who exercise, and 1.2 to 1.5 g per kg for most older adults with acute or chronic disease. People with severe kidney disease who are not on dialysis are an exception and may need less (PROT-AGE position paper, 2013).

For a 70 kg person, that is the difference between 56 g a day at the RDA and 84 g at 1.2 g per kg. Use our protein calculator to see where you land, and our calorie calculator to check that your energy intake can support muscle gain at all. If you struggle to reach your target, our guides to protein powder and high-protein snacks are more useful starting points than another supplement.

Creatine and GLP-1 weight-loss medicines

People losing weight on semaglutide or tirzepatide often ask about creatine to protect muscle. Evidence in people taking these medicines is very limited, so any benefit is largely an extrapolation from trials in other groups. What the evidence does support for preserving muscle during weight loss is adequate protein and regular resistance training. Our guide to GLP-1 weight loss covers these priorities in detail, and our weight management hub explains how dietitians support people on these medicines.

Downsides, side effects and who should be careful

Weight gain

ODS says the only consistent side effect is weight gain, with several studies finding a 1 to 2 kg rise in total body weight in a month of strength training with creatine. The ISSN describes short-term fluid retention of about 0.5 to 1.0 litre during loading. That explains the common question "why did I gain 10 pounds after taking creatine?" Water and new muscle can explain a few pounds, but a gain of 4 to 5 kg is more than the trials report, so look at changes in diet, training and fluid balance too.

Kidneys

The ISSN concludes there is "no compelling evidence that creatine supplementation negatively affects renal function in healthy or clinical populations", and notes that doses up to 30 g a day for up to five years in patient groups have not been linked to more kidney problems. It also acknowledges that some advise people with existing kidney disease to consult a doctor first. That advice is sensible: creatine breaks down into creatinine, which is the marker most kidney blood tests use, so tell your doctor you take it before any blood test.

Hair loss

The worry comes from a 2009 study in young male athletes that reported a rise in conversion of testosterone to DHT, a hormone linked to hair loss; it did not measure hair. A 2025 randomised trial in 45 resistance-trained men taking 5 g a day for 12 weeks found no differences in DHT or in hair measures compared with placebo, and the authors described this as "strong evidence against the claim" (Lak et al., Journal of the International Society of Sports Nutrition, 2025). It was small and short, and it did not include women or men already losing hair.

Other reported effects

ODS lists anecdotal reports of nausea, diarrhoea, muscle cramps and heat intolerance, and says creatine is considered safe for short-term use by healthy adults, with evidence that several years of use is safe.

Who should get advice first

• people with kidney disease or reduced kidney function;
• people with diabetes, liver disease or other long-term conditions on regular medicines;
• anyone pregnant or breastfeeding, because evidence is limited;
• children and teenagers, whose needs are best met by food and training;
• competitive athletes subject to anti-doping testing, who need a batch-tested product.

Women can take creatine too. The ISSN notes benefits in both sexes but that most studies were in men, and some suggest women gain less strength or muscle in response. Our separate guide to creatine for women looks at the evidence specific to women, and our guide to creatine side effects goes deeper into the gut, water and blood-test questions.

What happens if you take creatine every day

Daily use is the normal pattern in the trials, not a risk in itself. After about a month of 3 to 5 g a day, muscle stores plateau and further intake simply maintains them. If you stop, the ISSN says stores generally take 4 to 6 weeks to return to baseline, and there is no evidence they fall below it, so your own creatine production is not suppressed. Cycling on and off has no proven benefit.

Taken every day, creatine monohydrate typically leads to:

1. a small, early rise in body weight from water;
2. slightly more repetitions or power in hard sets;
3. over months of training, modestly greater gains in strength and lean mass than training alone.

It will not replace adequate food, sleep and progressive training. If you are not training, the case for taking it is weak.

Buying creatine: what the label can and cannot tell you

In the US, the FDA "is not authorized to approve dietary supplements for safety and effectiveness before they are marketed" (US Food and Drug Administration). ODS notes that some manufacturers use third-party certification companies to verify that sports supplements contain the labelled amounts and are free of many banned substances, naming NSF's Certified for Sport programme, Informed-Choice and the Banned Substances Control Group. A certification mark tells you the contents match the label. It does not tell you the product works better than any other creatine monohydrate.

When you compare products, look for:

• creatine monohydrate as the only active ingredient;
• a clear dose per serving, ideally 3 to 5 g;
• an independent testing mark, especially if you compete;
• no added stimulants, "proprietary blends" or testosterone boosters.

Price varies far more than quality. Our supplements hub explains how to judge other products on the same principles. For a personal plan that fits creatine, protein and training around your health conditions and medicines, book a session with a sports or clinical dietitian.

Try the free protein calculator