Medical Safety of Creatine Supplementation – Part 4 of 5

Medical Safety of Creatine Supplementation: While the only clinically significant side effect reported in the research literature is that of weight gain, many anecdotal claims of side effects including dehydration, cramping, kidney and liver damage, musculoskeletal injury, gastrointestinal distress, and anterior (leg) compartment syndrome still exist in the media and popular literature.

While athletes who are taking creatine monohydrate may experience these symptoms, the scientific literature suggests that these athletes have no greater, and a possibly lower, risk of these symptoms than those not supplementing with creatine monohydrate.

Many of these fears have been generated by the media and data taken from case studies (n = 1). Poortmans and Francaux reported that the claims of deleterious effects of creatine supplements on renal function began in 1998.

These claims followed a report that creatine supplementation was detrimental to renal glomerular filtration rate (GFR) in a 25-year-old man who had previously presented with kidney disease (glomerulosclerosis and corticosteroid-responsive nephritic syndrome).

Three days later, a French sports newspaper, L’Equipe, reported that supplemental creatine is dangerous for the kidneys in any condition. Several European newspapers then picked up the “news” and reported the same. Since that time, other individual case studies have been published posing that creatine monohydrate supplementation caused deleterious effects on renal function.

Much of the concern about creatine monohydrate supplementation and renal function has centered around concerns over increased serum creatinine levels. While creatinine does make up a portion of GFR and must be excreted by the kidneys, there is no evidence to support the notion that normal creatine intakes(less than 25 g/d) in healthy adults cause renal dysfunction.

In fact, Poortmans et al. have shown no detrimental effects of short- (5 days), medium- (14 days), or long-term (10 months to 5 years) creatine monohydrate supplementation on renal function.

Interestingly, Kreider et al. observed no significant difference in creatinine levels between creatine monohydrate users and controls, yet most athletes (regardless of whether taking creatine monohydrate or not) had elevated creatinine levels along with proper clearance during intense training. The authors noted that if serum creatinine was examined as the sole measure of renal function, it would appear that nearly all of the athletes (regardless of creatine monohydrate usage) were experiencing renal distress.

Although case studies have reported problems, these large-scale, controlled studies have shown no evidence indicating that creatine monohydrate supplementation in healthy individuals is a detriment to kidney functioning.

Another anecdotal complaint about supplemental creatine is that the long-term effects are not known.

Widespread use of creatine monohydrate began in the 1990′s. Over the last few years a number of researchers have begun to release results of long-term safety trials. So far, no long-term side effects have been observed in athletes (up to 5 years), infants with creatine synthesis deficiency (up to 3 years), or in clinical patient populations (up to 5 years).

One cohort of patients taking 1.5 – 3 grams/day of creatine monohydrate has been monitored since 1981 with no significant side effects.

In addition, research has demonstrated a number of potentially helpful clinical uses of creatine monohydrate in heart patients, infants and patients with creatine synthesis deficiency, patients suffering orthopaedic injury, and patients with various neuromuscular diseases.

Potential medical uses of supplemental creatine have been investigated since the mid 1970s. Initially, research focused on the role of creatine monohydrate and/or creatine phosphate in reducing heart arrhythmias and/or improving heart function during ischemic events.

Interest in medical uses of creatine supplements has expanded to include those with creatine deficiencies, brain and/or spinal cord injuries, muscular dystrophy, diabetes, high cholesterol/triglyceride levels, and pulmonary disease among others.

Although more research is needed to determine the extent of the clinical utility, some promising results have been reported in a number of studies suggesting that creatine supplements may have therapeutic benefit in certain patient populations.

In conjunction with short- and long-term studies in healthy populations, this evidence suggests that creatine supplementation appears to be safe when taken within recommended usage guidelines.

Reproduced with minor omissions, including references for ease of reading, from: Buford TW, Kreider RB, Stout JR, Greenwood M, Campbell B, Spano M, Ziegenfuss T, Lopez H, Landis J, Antonio J. International Society of Sports Nutrition position stand: creatine supplementation and exercise. Journal of the International Society of Sports Nutrition 2007, 4:6 (30 August 2007). doi:10.1186/1550-2783-4-6. © 2007 Buford et al; licensee BioMed Central Ltd.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (

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Creatine Side Effects: Myths and Safety Profile – Part 1 of 5
Facts and Benefits of Creatine – Part 2 of 5
The Best Creatine? Creatine Monohydrate Effectiveness – Part 3 of 5
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