Are there negative side effects to creatine? The Science vs. The Myths

November 20, 2025 •

3 min read

With hundreds of published studies supporting its safety and effectiveness, creatine is one of the most researched sports supplements available. However, widespread misinformation and anecdotal reports have fueled persistent questions about potential negative side effects to creatine, from kidney damage to hair loss.

Quick Summary

Creatine is one of the safest and most effective supplements, with most reported negative effects being debunked myths. For healthy individuals, it does not cause kidney damage, dehydration, or hair loss when used correctly.

Key Points

Creatine is safe for healthy kidneys: Extensive research shows creatine does not harm kidney or liver function in healthy individuals at recommended doses, despite temporary increases in creatinine levels.
Dehydration and cramps are myths: Studies show creatine does not cause dehydration or muscle cramps; it may even improve hydration status by increasing total body water.
Hair loss link is unfounded: The belief that creatine causes hair loss is based on a small, flawed study, and subsequent research has found no evidence to support this claim.
Weight gain is water and muscle, not fat: Initial weight gain from creatine is due to water retention in the muscles, with long-term gains being lean muscle mass.
High doses can cause GI upset: Gastrointestinal issues like bloating or diarrhea are rare and most often tied to high, single doses, such as during a loading phase.
Loading phase is not essential: You can skip the higher-dose loading phase and simply take a daily maintenance dose of 3-5g to achieve the same results over time, minimizing potential GI issues.

Creatine: An Overview

Creatine is a naturally occurring compound found primarily in muscle cells, playing a key role in energy production, especially during high-intensity exercise. The body produces it from amino acids and it's also found in foods like meat and fish. Supplementation increases phosphocreatine stores, which helps regenerate ATP, the primary energy source for muscles. This can improve strength, power, and muscle mass.

Debunking the Top Creatine Myths

Years of research have repeatedly disproven many common fears surrounding creatine use in healthy individuals following recommended dosages.

Myth 1: Creatine damages the kidneys and liver

This common myth is based on a misunderstanding of creatine metabolism. Creatine breaks down into creatinine, a harmless waste product filtered by the kidneys. While supplementation causes a temporary rise in blood creatinine, numerous studies (up to 5 years) show no harm to kidney or liver function in healthy individuals. The concern is primarily for those with pre-existing kidney disease.

Myth 2: Creatine causes dehydration and muscle cramps

Extensive studies show creatine does not cause dehydration or muscle cramps. While it pulls water into muscle cells, it doesn't negatively affect overall hydration. Some research even suggests it might improve hydration and help prevent cramps, especially in hot conditions. Adequate daily water intake remains important for general health.

Myth 3: Creatine causes hair loss

This claim stems from a small 2009 study showing an increase in DHT (linked to baldness) in rugby players, but it didn't measure actual hair loss, and levels were still normal. Multiple subsequent studies have found no link between creatine and hair loss.

Myth 4: Creatine is a steroid

Creatine is a natural compound made of amino acids, chemically distinct from anabolic steroids. It is legal and not banned by major athletic organizations like WADA.

Actual, Manageable Side Effects

Some minor, dose-dependent issues can occur, but are typically manageable.

Temporary Water Weight Gain: Initial weight gain is common due to water retention in muscle cells, which subsides. Long-term gain is due to increased muscle mass.
Gastrointestinal Discomfort: High doses can cause stomach upset, bloating, or diarrhea in a small percentage. Splitting doses or skipping the loading phase minimizes this risk.

Comparison of Creatine Myths vs. Facts


Claim	Myth	Scientific Fact
Kidney Damage	Creatine harms the kidneys by forcing them to overwork filtering a waste product.	Healthy kidneys are fully capable of filtering excess creatinine. Decades of research show no harm to healthy kidneys at recommended doses.
Dehydration	Creatine pulls water from the body, causing dehydration and cramps.	Creatine pulls water into muscle cells, increasing total body water. This does not cause dehydration and may even improve hydration status.
Hair Loss	Creatine elevates DHT, causing baldness.	No causal link found in extensive research. The myth is based on a small study, and many subsequent studies have shown no effect on hormones or hair loss.
Weight Gain	Creatine causes you to gain fat and look bloated.	Initial weight gain is water retention inside muscles. Long-term weight gain is increased lean muscle mass, not fat.
Digestive Issues	Stomach upset is a guaranteed side effect of creatine use.	Gastrointestinal issues are rare and typically only occur with excessive, single doses, such as during a heavy loading phase.

How to take creatine safely and effectively

For most healthy adults, creatine monohydrate is safe and effective. Follow these guidelines:

Stick to recommended dosage. 3–5 grams per day is sufficient. The loading phase is optional and can be skipped to avoid potential stomach upset.
Choose a quality product. Look for reputable brands with third-party testing like Creapure®.
Stay hydrated. Maintain adequate fluid intake for performance and health.
Consult a professional if needed. Speak with a healthcare provider if you have pre-existing medical conditions or are taking medications.

Conclusion

Scientific evidence overwhelmingly supports creatine as a safe and effective supplement for healthy individuals. Most supposed negative effects, such as kidney damage, dehydration, and hair loss, are debunked myths. The only potential downsides are minor, temporary water weight gain and possible gastrointestinal distress from high doses, both manageable. By choosing a quality product, following recommended dosages, and staying hydrated, you can confidently enjoy creatine's benefits. For further details, consult the International Society of Sports Nutrition position stand.

Frequently Asked Questions

For healthy individuals, creatine is not bad for the kidneys. The concern stems from the fact that creatine supplementation can temporarily increase creatinine levels in the blood, which is a normal byproduct, not a sign of kidney damage.

No, the link between creatine and hair loss has been debunked. The myth is based on a single small study, and the vast majority of research shows no connection between creatine supplementation and hair loss.

Creatine can cause temporary water retention inside muscle cells, which might lead to a slight feeling of puffiness or bloating, particularly during an initial loading phase. This effect is manageable and typically subsides once you transition to a lower, maintenance dose.

No, extensive research has disproven the myth that creatine causes dehydration or muscle cramps. In fact, it can help increase total body water, potentially aiding in hydration and reducing the risk of cramping.

No, a loading phase is not necessary. While it saturates your muscles with creatine faster, taking a standard 3–5g maintenance dose daily will achieve the same level of saturation over a longer period, without the potential for gastrointestinal side effects.

If you are taking medications, particularly those that affect the kidneys or blood sugar, it is recommended to consult a healthcare provider before starting creatine supplementation. Certain interactions, such as with high-dose caffeine, have been noted.

Yes, long-term creatine use is considered safe for healthy individuals. Studies lasting several years have found no adverse health effects, even with high doses.