What Happens to Your Body When You Take Too Much Creatine

Everywhere you turn, creatine is making headlines. It’s the supplement of the moment, and many would argue its popularity is for good reason. Creatine is one of the most-studied supplements for athletes and active individuals, with studies indicating significant performance benefits. “Creatine helps replenish your muscles’ energy during high-intensity activities like interval running or heavy weightlifting, allowing you to keep going,” says Marita Radloff, M.S., RDN, LD. “Some of the athletic benefits of taking creatine include increased muscle strength and size, improved endurance, increased power and jump performance, and fatigue resistance.” Studies have not only shown that it’s effective for improving performance, but emerging research indicates it may benefit the brain.

Because of its popularity, some may be led to believe there’s no limit to its effects and might take a “more is better” approach. However, as with anything, you can get too much of a good thing. We turned to the experts to ask a simple question: What happens when you get too much creatine? Let’s break it down.

Is Creatine Safe?

“Creatine is one of the most-studied supplements and is generally considered very safe,” says Radloff. A 2021 review of creatine found that more than 1,000 studies have investigated the effects of creatine on health and performance. Major sports nutrition and general nutrition practice groups, like the Academy of Nutrition and Dietetics and the International Society of Sports Nutrition, have stated that creatine is a safe and effective supplement for sports performance. In addition, a recently published analysis of side effects from creatine reported in more than 600 studies found that creatine supplementation did not result in more side effects.

Recommended Dosage

The most common recommendation you’ll see for creatine dosage is 3 to 5 grams per day, but it can go up to 20 grams per day, according to Jennifer O’Donnell-Giles, M.S., RDN. “For most of my athletes I recommend 5 to 10 grams per day,” she says. But some people may take more creatine depending on the reason for adding the supplement. For example, some research on brain creatine levels shows that higher doses may be necessary to increase effectiveness for treating certain chronic conditions. Research is also ongoing regarding the effective dose of creatine for improved cognitive functioning in healthy individuals. Working with a health professional is advised before adding creatine above generally recommended doses.

Is Creatine Loading Necessary?

A creatine loading phase is where you take higher dosages of creatine for the first week. But, according to O’Donnell-Giles, the practice is somewhat controversial. “I do not recommend loading,” she says. “I recommend starting at 5 grams per day and after a few months decide to increase or not based on the individual’s response and overall goals.” A recent summary on the safety and effectiveness of creatine backs this approach, concluding that a loading phase is not required and starting with 3 to 5 grams per day is effective.

Potential Risks of Too Much Creatine

Creatine has been tested extensively, and research continues to show it has minimal side effects when taken in recommended doses. “Even with long-term use, few side effects have been reported in healthy individuals,” says Valarie Hannahs, M.S., RD, LD. “The most common effect is a small, temporary increase in water retention as muscles store more creatine—this is normal and can actually help with muscle hydration and performance.” Still, some additional side effects have been reported in rare cases.

• Digestive Distress: “Very high dosages (over 20 grams per day) may lead to GI distress (diarrhea, nausea, stomach cramps),” says O’Donnell-Giles. Creatine can draw water into the digestive tract, which can result in uncomfortable digestive symptoms.
• Water Retention: “Water retention often happens as well, which can cause temporary weight gain,” says O’Donnell-Giles. However, many experts say this effect is temporary and subsides within the first few weeks of supplementation.
• Muscle Cramping: Another reported side effect of creatine is muscle cramping, but the research has not backed this claim. In fact, some research shows creatine can offer benefits for preventing muscle cramps. Still other studies have found that the incidence of muscle cramping in those taking creatine supplements is not significantly different from those taking placebo.
• Kidney-Related Issues: Contrary to popular belief, creatine has not shown to cause kidney- or liver-related issues in healthy populations when taken at recommended doses.
• Other Ingredient Interaction: Some creatine supplements are single-ingredient products with just creatine, but others combine performance-enhancing substances like caffeine to boost performance benefits. Taking more than the recommended dose of creatine when other ingredients are present could cause negative outcomes. “If you take a creatine supplement that also has caffeine or another stimulant, that could cause overdoing it on caffeine,” says Radloff. Carefully review the label to ensure you’re aware of the ingredients present in the creatine supplement and how to take it safely without side effects.

When to Consult a Health Professional

While side effects of taking creatine are rare, when an individual takes more than the recommended dosage, it’s possible they may experience negative effects that should be considered before continuing the supplement. “Signs and symptoms of too much creatine include bloating, stomach cramping, possible muscle cramps (but this is linked to dehydration while taking creatine), nausea, diarrhea, temporary water retention and possible increase in thirst (also associated with effects of dehydration),” says O’Donnell-Giles. If any of these symptoms persist or do not subside after stopping the supplement, it’s recommended to seek health advice from a medical professional.

Tips for Safely Using Creatine

The supplement market is often criticized for its lack of oversight leading to discrepancies in supplement ingredients, false labeling and quality concerns. When choosing a creatine supplement, O’Donnell-Giles recommends looking for creatine monohydrate as the only ingredient while also avoiding blends and proprietary formulas. 

“The product should always be third-party tested and labeled as Certified for Sport (NSF logo will be on the product bottle),” she says. “When in doubt, check the informed choice website and make sure it’s listed on there and the NSF website. This will ensure safety and efficacy of the product.” 

Beyond ensuring the supplement you choose is independently tested for quality and safety, you should also only take the recommended dose unless a health professional, like a registered dietitian, has indicated otherwise.  

Our Expert Take

Creatine is a sports nutrition supplement that’s been extensively studied and proven effective for performance. While side effects are rare, some may occur, particularly when creatine is taken above recommended doses or when combined with other supplements like caffeine at high doses. “Creatine can cause side effects in some individuals, including water retention, nausea, stomach cramps and diarrhea,” says Anna Mitchell, M.S., RDN. “These side effects may be worse in individuals taking too much creatine.”

When choosing to supplement with creatine, experts recommend a supplement with the single ingredient of creatine monohydrate. It’s also recommended to choose only independently tested supplements and to take only the recommended dose for safety.