For decades, creatine has been a staple in strength training, bodybuilding, and other explosive sports. It is known for its effect on strength, muscle mass, and training output. At the same time, long-term use raises questions. Is it safe to use creatine for months or even years? And what does that mean for your kidneys, liver, blood pressure, and general health? In this blog, you will get an informed answer. We look at long-term studies, position statements from international sports nutrition organizations, and common concerns from practice. This will help you better assess what creatine does and does not do in the long term.
What does science say about long-term use?
For healthy athletes, creatine monohydrate is considered safe when used within the common dosage of 3–5 grams per day. This conclusion does not come from a single study, but from dozens of RCTs, cohort studies, and multiple review articles. The International Society of Sports Nutrition (ISSN) concludes that there is no convincing evidence of negative health effects from long-term use within these dosages (Kreider et al., 2017).
Long-term studies, ranging from several months to several years, show no structural health damage in adults without underlying conditions.
Creatine and kidney function
A common concern is that creatine could strain the kidneys. Controlled studies do not support this. Studies up to 12 months show no deterioration of eGFR or creatinine clearance in creatine users compared to placebo (Chilibeck et al., 2015). Field studies in athletes with long-term use (up to approximately 21 months) also show no increased risk of kidney problems (Kreider et al., 2003).
It is important to understand that creatine can slightly increase serum creatinine, because a small part of creatine is converted into creatinine. This is a laboratory effect, not an indication of kidney damage. When undergoing blood tests, it is advisable to mention that you are using creatine.
Effects on liver, blood pressure, and cholesterol
No consistent negative effects have been found for the liver either. Year-long studies show that liver enzymes (such as ALT and AST) remain within normal values with creatine supplementation (Chilibeck et al., 2015).
The same applies to blood pressure and blood lipids. The available literature mainly reports neutral effects. No structural link has been found between creatine use and increased blood pressure or unfavorable changes in the cholesterol profile (Kreider et al., 2003).
Concerns from practice
Cramps and dehydration
Creatine increases the intracellular water content in muscle cells. As a result, body weight often increases by 1–2 kg in the first few weeks. This is unrelated to dehydration. In athletic cohorts, even fewer cramps and heat-related complaints were reported among creatine users (Greenwood et al., 2003).
Hair loss and DHT
One small study showed an increase in DHT after a high loading phase, but these values remained within the normal range and have never been convincingly replicated. Review studies find no consistent effect of creatine on testosterone or DHT (Antonio et al., 2021).
Stomach and intestinal complaints
Some users experience stomach complaints, usually with high single doses or poor dissolution. Spreading intake throughout the day and dissolving well in water reduces this risk. In controlled studies, these complaints are no more common than with placebo (Kreider et al., 2017).
How to use creatine safely in the long term?
Creatine monohydrate is the most researched and best-supported form. Other variants show no demonstrable advantage.
You can choose between two strategies. Without a loading phase, you take 3–5 grams per day; after about four weeks, muscles are saturated. With a loading phase, you take approximately 20 grams per day for 5–7 days, divided into multiple intakes, followed by 3–5 grams maintenance.
The timing of intake is less important than consistent daily use. Dissolving in water or combining with a meal is fine. Sufficient hydration remains important, especially during intensive training.
When should you be extra careful?
Do you have a known kidney or liver condition, are you using medication that affects kidney function, or are you pregnant or breastfeeding? Then consultation with a doctor is advisable before using creatine. For healthy adults without medical indications, this restriction generally does not apply (NIH).
Conclusion: Is creatine safe in the long term?
Creatine is one of the most researched supplements in sports nutrition. For healthy athletes, long-term use is safe within a daily dosage of 3–5 grams. Long-term studies show no clinically relevant negative effects on kidney function, liver enzymes, blood pressure, or blood lipids. Common concerns such as cramps, dehydration, or hair loss are not supported by strong evidence. Use creatine monohydrate, hydrate sufficiently, and be consistent. That is what the data supports.
Frequently asked questions about whether creatine is safe in the long term
Is creatine bad for your kidneys in the long term?
In healthy individuals, long-term studies show no deterioration of kidney function with a daily intake of 3–5 grams. A slight increase in creatinine in blood tests is not kidney damage.
Can you use creatine for years?
Yes, in healthy athletes, long-term use is safe within the standard dosage. There is no need to cycle off for safety reasons.
Does creatine cause dehydration or cramps?
No, research does not indicate this. Creatine increases the water content in muscle cells but does not increase the risk of dehydration.
Is a loading phase necessary for safe use?
No. Without a loading phase, you will achieve the same effect after a few weeks. A loading phase accelerates the process but is not essential.
Sources:
Antonio, J., et al. (2021). Common questions and misconceptions about creatine supplementation. Journal of the International Society of Sports Nutrition, 18(1). https://www.tandfonline.com/doi/full/10.1186/s12970-021-00412-w
Chilibeck, P. D., et al. (2015). Effects of creatine and resistance training on muscle mass and health. Medicine & Science in Sports & Exercise, 47(8). https://journals.lww.com/acsm-msse/fulltext/2015/08000/effects_of_creatine_and_resistance_training_on.5.aspx
Greenwood, M., et al. (2003). Cramping and injury incidence in athletes supplementing with creatine. Journal of Athletic Training, 38(3). https://pmc.ncbi.nlm.nih.gov/articles/PMC155512/
Kreider, R. B., et al. (2003). Long-term creatine supplementation does not significantly affect clinical markers of health. Molecular and Cellular Biochemistry. https://pubmed.ncbi.nlm.nih.gov/12701816/
Kreider, R. B., et al. (2017). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation. Journal of the International Society of Sports Nutrition, 14(1). https://www.tandfonline.com/doi/full/10.1186/s12970-017-0173-z
van der Merwe, J., et al. (2009). Effects of creatine supplementation on DHT levels. https://pubmed.ncbi.nlm.nih.gov/19741313/
