Should I stop taking creatine in summer?

No. The evidence does not support pausing creatine for hot-weather training. The 2009 Lopez systematic review, the Greenwood NCAA football data, and the ISSN position stand all found no increase in heat illness, dehydration, or cramping incidence among creatine users. Keep your standard 3 to 5 g daily dose year round.

Does creatine actually dehydrate you?

No. Creatine increases intracellular water content in muscle cells, but it does this by causing the body to retain slightly more total fluid, not by pulling water from plasma. Controlled studies show total body water and plasma volume are equal or slightly higher in creatine users than in placebo users. Sweating capacity is not impaired.

Does creatine cause muscle cramps?

The controlled evidence says no. Across three seasons of NCAA Division IA football data, creatine users had equal or lower rates of cramping than non-users. The modern understanding of exercise-associated cramping points to neuromuscular fatigue and prior cramping history as the dominant risk factors, not creatine status.

Do I need to drink more water on creatine?

Drink normally to thirst. The advice to dramatically over-hydrate on creatine is not supported by evidence and can be counterproductive. Keep urine pale yellow and replace sodium during heavy sweating. The standard hot-weather hydration guidance applies whether or not you are supplementing.

Why do people still say creatine causes heat illness?

The warning originated from late-1990s case reports involving college wrestlers who died during extreme weight-cutting attempts in hot environments. Creatine was a plausible suspect at the time because it was new and visible, but no causal link was ever established, and the controlled research since then has consistently failed to confirm the dehydration-cramps story. The advice persists in coaching circles and some older athletic training materials, but it is not supported by the current evidence.

What about creatine for athletes who cut weight (wrestlers, MMA, boxers)?

Combat sport athletes who need to make a tight weight class often pause creatine in the final 2 to 3 weeks before weigh-in. The reasoning is mechanical, not safety-driven: creatine adds a small amount of intracellular water that makes weight cutting marginally harder. The relevant risk in those deaths was extreme dehydration to make weight, not creatine itself.

Is there a safer creatine form for summer?

No. Creatine monohydrate is the most-studied form and has no special risk profile in heat. Buffered creatines, creatine HCl, and other variants do not have a meaningful safety advantage and are typically more expensive without better effectiveness data. See our creatine HCl vs monohydrate breakdown for the full comparison.

Creatine in Summer Heat: Does It Cause Dehydration or Cramps? (2026)

The Short Version

Creatine does not increase your risk of dehydration, heat illness, or muscle cramps when training in summer heat. That conclusion is supported by a 2009 systematic review in the Journal of Athletic Training, three seasons of NCAA Division IA football injury data published by Greenwood and colleagues in 2003, the 2017 International Society of Sports Nutrition position stand, and the 2021 ISSN "common questions" review. Every major review of the evidence has reached the same conclusion. The dehydration-and-cramps story is a cultural holdover from the late 1990s that the data has not supported for over two decades.

This piece walks through where the myth came from, what the studies actually measured, the mechanism (why creatine plausibly helps with heat tolerance rather than hurting it), and how to think about summer training while supplementing.

Where the Myth Came From

In 1997 and 1998, three college wrestlers died during weight-cutting attempts in hot environments. None of the deaths were attributed to creatine, but two of the athletes had reported creatine use, and the supplement was new and visible enough that the FDA released a public letter raising concerns. Several early NCAA position statements echoed the caution.

The mechanism people proposed was reasonable on paper. Creatine pulls water into muscle cells. If water is being sequestered intracellularly, the argument went, then plasma volume and sweating capacity might fall, raising the risk of heat illness and cramping. It was a plausible hypothesis. It was not a finding from a controlled study, and the moment researchers started running those studies in the early 2000s, the hypothesis stopped holding up.

What the Studies Actually Show

The 2009 J Athl Train systematic review (Lopez et al.)

Lopez and colleagues pooled the controlled studies that had measured thermoregulation, plasma volume, sweat rate, core temperature, and hydration markers in creatine users versus placebo. The conclusion was direct: "No evidence supports the concept that creatine supplementation either hinders the body's ability to dissipate heat or negatively affects the athlete's body fluid balance." Several individual studies in the review found that total body water actually increased with creatine, including extracellular water, which is the compartment that matters for thermoregulation.

The 2003 NCAA football data (Greenwood et al.)

Greenwood and colleagues tracked NCAA Division IA football players across three seasons (1998 through 2000), with creatine use ranging from 34% to 56% of players in any given season. They counted cramping episodes, heat illness, muscle strains, joint injuries, and missed-practice events, then compared incidence rates between creatine users and non-users. Across every category, creatine users had equal or lower rates than non-users. Cramping incidence was 37 events across 96 instances. Heat or dehydration incidents totaled 8 across 28 instances. In every category the creatine group was overrepresented in the denominator (they were on creatine) but never overrepresented in the numerator (the injuries). The authors concluded that supplementation "does not appear to increase the incidence of injury or cramping" in college football, which is roughly the hardest hot-weather training environment in American sport.

The ISSN position stand (Kreider et al., 2017)

The International Society of Sports Nutrition position stand reviewed the safety data and concluded that short- and long-term supplementation (up to 30 g per day for five years) is "safe and well-tolerated" in healthy individuals. Heat tolerance, cramping, and hydration were specifically examined. The ISSN found no evidence of harm and suggested that the slight increase in total body water could plausibly support thermoregulation rather than impair it.

Antonio et al. 2021 "common questions"

The Antonio and colleagues 2021 review in JISSN was specifically structured around persistent creatine myths. On dehydration and cramping the conclusion is the same: the evidence does not support the claim. The authors note that creatine has been studied in over 500 peer-reviewed trials, and the heat tolerance and hydration story is one of the most thoroughly investigated and most consistently negative findings in the literature.

The Mechanism (Why It Would Make Sense for Creatine to Help, Not Hurt)

Creatine increases intracellular water content in skeletal muscle. The amount is small in absolute terms (roughly 1 to 2 liters of total body water over the first several weeks of supplementation), and the body responds to it by retaining slightly more total fluid, not by pulling fluid out of the extracellular compartments. Plasma volume in creatine users is generally equal to or slightly higher than in placebo users.

For thermoregulation, what matters is the ability to sweat (which requires fluid in the plasma and interstitial space) and the cardiovascular capacity to move blood to the skin. Both of those depend on extracellular fluid, which creatine does not deplete. The intracellular water creatine adds is sequestered inside muscle cells and is not drawn on for sweating.

The plausible heat-tolerance mechanism, suggested in several of the controlled studies, is that creatine users carry more total water, which gives them a slightly larger heat-buffering reservoir. This is not a strong or clinically meaningful effect, but it points the opposite direction from the dehydration story.

What Actually Causes Exercise-Associated Cramps

The cramping literature has shifted substantially over the last fifteen years. The older "electrolyte and dehydration" theory has largely been replaced by a "neuromuscular fatigue" model. Cramps in trained athletes correlate more strongly with novel training load, prior cramping history, and accumulated neuromuscular fatigue than with sweat sodium loss or hydration status. Most controlled rehydration trials have failed to reliably prevent cramps in athletes prone to them.

The practical implication: if you cramp in heat, the highest-yield interventions are pacing the work, replacing sodium (not just water), and building heat acclimatization over 10 to 14 days. Creatine is essentially a non-factor in this equation in either direction.

Practical Guidance for Summer Training on Creatine

Dose stays the same. 3 to 5 g per day of creatine monohydrate, year round. There is no reason to cycle off in summer.
Drink to thirst, plus sodium. The standard hydration guidance for hot-weather training applies whether or not you are taking creatine. Sodium intake matters more than total water volume for most people sweating heavily. Our electrolyte powders comparison covers sodium dosing for different sweat profiles.
Acclimatize. The single most protective factor for heat illness is 10 to 14 days of progressive heat exposure. Creatine does not shortcut this and does not block it.
Watch loading-phase GI symptoms. The one creatine-specific issue in summer is that some users get mild GI distress during a 20 g per day loading phase. Splitting doses (4 x 5 g) usually resolves it. A standard 5 g per day with no loading phase reaches full saturation in 3 to 4 weeks with essentially no GI burden.
Forget the "drink an extra gallon" advice. The recommendation to drastically over-hydrate while on creatine is not based on evidence. Drinking enough to keep urine pale yellow is fine. Forced over-hydration carries its own risks, including hyponatremia in extreme cases.

The One Real Edge Case: Combat Sports and Weight Cutting

The 1997-1998 wrestler deaths happened during extreme dehydration attempts to make weight. Cutting water weight aggressively while in a hot environment, regardless of supplement status, carries real risk. Creatine adds a small amount of intracellular water, which makes it slightly harder to cut weight by dehydration. For combat sport athletes who weigh in tight to a weight class, this is a relevant consideration, but it is a competition-prep issue, not a safety issue. Most coaches in MMA, boxing, and wrestling have athletes pause creatine in the final 2 to 3 weeks before weigh-in for that reason. This is about gaming the scale, not about heat tolerance.

The Bottom Line

The dehydration-and-cramps warning attached to creatine in summer is a holdover from late-1990s case reports that subsequent controlled research has failed to confirm. Every major review since 2003 (Greenwood NCAA data, Lopez J Athl Train systematic review, the ISSN position stand, Antonio "common questions" review) has reached the same conclusion: creatine users do not have higher rates of heat illness, dehydration, or cramping than non-users. The plausible mechanism actually runs the opposite direction, with creatine increasing total body water and possibly providing a small thermoregulatory buffer.

If you are training in summer and considering whether to pause creatine, the evidence does not support that decision. Keep the 3 to 5 g daily dose, focus on the hydration and acclimatization fundamentals that matter for everyone in heat, and treat the dehydration story as an outdated assumption that the research has moved past.

Sources

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. J Athl Train. 2009;44(2):215-223. PMID: 19295968.
Greenwood M, Kreider RB, Melton C, Rasmussen C, Lancaster S, Cantler E, Milnor P, Almada A. Creatine supplementation during college football training does not increase the incidence of cramping or injury. Mol Cell Biochem. 2003;244(1-2):83-88. PMID: 12701814.
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. J Int Soc Sports Nutr. 2017;14:18. PMID: 28615996.
Antonio J, Candow DG, Forbes SC, et al. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? J Int Soc Sports Nutr. 2021;18(1):13. PMID: 33557850.

Does Creatine Cause Dehydration or Muscle Cramps in Summer Heat?