Long-term oral creatine supplementation does not impair renal function in healthy athletes. Med. Sci. Sports Exerc., Vol. 31, No. 8, pp. 1108-1110, 1999.
Purpose: Oral creatine supplementation is widely used in sportsmen and women. Side effects have been postulated, but no thorough investigations have been conducted to support these assertions. It is important to know whether long-term oral creatine supplementation has any detrimental effects on kidney function in healthy population.
Methods: Creatinine, urea, and plasma albumin clearances have been determined in oral creatine consumers (10 months to 5 yr) and in a control group.
Results: There were no statistical differences between the control group and the creatine consumer group for plasma contents and urine excretion rates for creatinine, urea, and albumin. Clearance of these compounds did not differ between the two groups. Thus, glomerular filtration rate, tubular reabsorption, and glomerular membrane permeability were normal in both groups.
Conclusions: Neither short-term, medium-term, nor long-term oral creatine supplements induce detrimental effects on the kidney of healthy individuals.
Chimie Physiologique, Institut Supérieur d'Education Physique et de Kinésithérapie, Université Libre de Bruxelles, Brussels, BELGIUM; and Laboratoire de Physiologie, Institut d'Education Physique et de Réadaptation, Université Catholique de Louvain, Louvain-la-Neuve, BELGIUM
Submitted for publication November 1998.
Accepted for publication January 1999.
Address for correspondence: Jacques R. Poortmans, Chimie Physiologique, ISEPK 168, Université Libre de Bruxelles, 28 avenue Paul Héger, B-1000 Bruxelles, Belgium. E-mail: email@example.com.