Does Creatine Make You Retain Water?
What creatine does to body water, how much weight to expect, and what the research says about cramps.
Short answer
Yes, mostly early on. Creatine causes water retention by pulling water into muscle, and a loading phase (about 20 g a day for 5 to 7 days) typically adds 1 to 3 kg of body mass, mostly water. Over longer periods the evidence is mixed: several 5 to 10 week studies found no significant change in total body water, and one 8 week trial found an increase. The water sits mainly inside muscle cells, not as a mystery layer of puffiness. Controlled trials haven't found that creatine causes dehydration or cramping.
Our creatine water intake calculator adds a small drinking cushion on top of your normal target.
Where the water goes
Creatine is osmotically active, which means it draws water with it. According to a 2021 review of common creatine questions in the Journal of the International Society of Sports Nutrition (retrieved via PubMed), muscle takes up creatine from the blood through a sodium-dependent transporter. Because that transport involves sodium, water follows into the muscle cell to keep the concentration balanced. So the extra water mostly lands inside muscle.
That's a different thing from the water you may retain after a salty meal, which sits outside cells. The same review notes that the pumps that control sodium inside cells make it unlikely that creatine changes sodium levels much.
How much weight to expect
The same 2021 review says the loading phase, about 20 g a day for 5 to 7 days, typically brings a 1 to 3 kg increase in body mass, mostly from water retained in the body. Early studies cited by the International Society of Sports Nutrition position stand reported short-term fluid retention of roughly 0.5 to 1.0 liter during loading. A 2006 trial (Watson et al., 12 active men, 21.6 g a day for 7 days) found body mass up 0.88 kg.
We didn't find a measurement of how much water you retain if you skip loading and take a steady daily dose, so we aren't giving a number for that.
| Situation | What was reported | Source |
|---|---|---|
| Loading, 20 g a day for 5 to 7 days | 1 to 3 kg gain in body mass, mostly water | 2021 JISSN review |
| Loading, short term | About 0.5 to 1.0 L of fluid retention | Early studies cited by the ISSN position stand |
| Training studies, 5 to 10 weeks | No significant increase in total body water in several trials | 2021 JISSN review |
| 28 days, healthy men and women | Body mass and total body water rose; intracellular and extracellular water volumes did not change significantly | 2021 JISSN review (Powers et al.) |
| 8 weeks plus resistance training | Total body water up 7.0% vs 1.7% on placebo; intracellular water up 9.2% vs 1.6% | 2021 JISSN review (Ribeiro et al.) |
The studies disagree, so we aren't giving you a single number for long-term retention. What they share is that the early jump is real, and that it settles into muscle.
Is it bloating or is it muscle water?
The research describes water entering muscle cells. The 2021 review points out that in the 8 week trial the ratio of skeletal muscle mass to intracellular water stayed the same in both groups, which fits with water moving in with muscle, not sitting outside it. We didn't find a study that measured visible puffiness under the skin, so we can't tell you creatine causes or doesn't cause that look.
If your stomach feels uncomfortable after taking it, that's a separate question from water retention, and stomach upset isn't what these sources are about.
Does it cause dehydration or cramps?
A common worry is that holding extra water in muscle leaves less for the rest of the body, especially when you sweat. The 2021 review lays out that theory. It also says surveys of athletes have found some report cramping. In one survey of 219 athletes, 90 used creatine and 34 of them reported perceived negative effects such as cramping.
The controlled evidence points the other way. The review says those surveys didn't control for other supplements or for dose. It then describes a hot, humid football season in which players who took creatine had significantly less cramping, heat illness and dehydration, along with fewer muscle strains, than players who did not. A systematic review with meta-analyses by Lopez and colleagues in the Journal of Athletic Training looked at heat tolerance and hydration status and didn't find that creatine hinders either. The ISSN position stand likewise reports no increase in cramping or dehydration.
That's reassuring but not a license to ignore your fluids. None of these sources give a specific extra amount of water to drink on creatine.
How much water should you drink on creatine?
We didn't find an official number. Our creatine water intake calculator starts from the same formula as the main daily water calculator, which is body weight times 32.5 mL plus 0.6 liters per hour of exercise, and then adds a cushion of 250 mL on maintenance or 500 mL while loading. That cushion is our own editorial margin, not a research result, and the calculator page says so. You can read how the base formula was built in Water Intake Formulas Compared.
If you lift in the heat, sweat a lot, or load, drink to thirst and check your urine color. Pale yellow or lighter is the target.
Most creatine safety research is in healthy people. If you have kidney disease or take medicines that affect your kidneys, ask your doctor before using creatine.
Reading the scale
Because the early gain is mostly water, a jump on the scale in the first week or two isn't fat. This is our interpretation of the sources, not a measurement we ran. If you track weight, compare like with like: the same time of day, the same scale, and an average over a week instead of a single morning.
Keep reading
- Creatine Water Intake CalculatorA water number for maintenance or loading.
- How Much Water Is Too Much?How overhydration happens and who is at risk.
- Do You Need Electrolytes?When plain water is enough and when electrolytes may help.
- Sweat Rate CalculatorFind your sweat rate from a weigh-in before and after a workout.
Frequently asked questions
How long does creatine water retention last?
The early gain shows up in the first days of loading. Beyond that, the studies we found disagree about whether total body water stays elevated. Several trials of 5 to 10 weeks found no significant increase, and an 8 week trial found one.
Does creatine make you look bloated?
We didn't find a study that measured visible puffiness. The research describes water moving into muscle cells. Stomach discomfort is a separate issue from water retention.
Do I have to load creatine?
No. The ISSN position stand describes a loading approach of about 5 g four times a day for 5 to 7 days followed by 3 to 5 g a day. The 2021 review says 3 to 5 grams a day for at least four weeks reaches a similar muscle level. The early weight jump described in the research is tied to the loading phase.
Does creatine dehydrate you?
Controlled trials and a meta-analysis didn't find that it does. Surveys of athletes report some cramping, but the 2021 review notes those surveys didn't control for other supplements or dose.
How much water should I drink on creatine?
No official figure exists in the sources we read. Our creatine calculator adds 250 mL on maintenance or 500 mL while loading to your usual target, and labels that as our own margin. Drink to thirst and watch your urine color.
Sources
- Antonio J, Candow DG, Forbes SC, et al. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? Journal of the International Society of Sports Nutrition 18(1):13, 2021. Citation details via PubMed: https://pubmed.ncbi.nlm.nih.gov/33557850/ (DOI 10.1186/s12970-021-00412-w). Full text on PubMed Central: PMC7871530
- 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 14:18, 2017. Citation details via PubMed: https://pubmed.ncbi.nlm.nih.gov/28615996/, DOI 10.1186/s12970-017-0173-z, full text on PubMed Central (PMC5469049)
- Lopez RM, Casa DJ, McDermott BP, Ganio MS, Armstrong LE, Maresh CM. Does creatine supplementation hinder exercise heat tolerance or hydration status? A systematic review with meta-analyses. Journal of Athletic Training 44(2):215 to 223. PubMed: https://pubmed.ncbi.nlm.nih.gov/19295968/
- Watson G, Casa DJ, Fiala KA, et al. Creatine use and exercise heat tolerance in dehydrated men. Journal of Athletic Training 41(1):18-29, 2006. Via PubMed: https://pubmed.ncbi.nlm.nih.gov/16619091/
How this page was built. This guide was drafted with AI assistance for Daily Water Calculator. The full text of the 2021 review of common creatine questions and of the International Society of Sports Nutrition position stand, both on PubMed Central, was searched for the points cited here. The Lopez meta-analysis and the Watson trial were read as PubMed abstracts. The studies disagree on long-term water retention, and the page says so instead of picking a side. The 250 mL and 500 mL cushion in our creatine calculator is our own editorial margin, not a research result. We revisit the sources when the calculator is updated. Last reviewed: .
General information for healthy adults, not medical advice. If you are pregnant or breastfeeding, or you have kidney, heart or liver conditions or a fluid limit, ask a clinician first. Terms and medical disclaimer.