- Med Hypotheses. 2000 May;54(5):726-8 - PubMed
- J Fam Pract. 2001 Aug;50(8):696-9 - PubMed
- Lancet. 1998 Jul 18;352(9123):234 - PubMed
- Rheumatology (Oxford). 2000 Mar;39(3):293-8 - PubMed
- Neurol Res. 2000 Mar;22(2):145-50 - PubMed
Creatine has been reported to be an effective ergogenic aid for athletes. However, concerns have been raised regarding the long-term safety of creatine supplementation. This study examined the effects of long-term creatine supplementation on a 69-item panel of serum, whole blood, and urinary markers of clinical health status in athletes. Over a 21-month period, 98 Division IA college football players were administered in an open label manner creatine or non-creatine containing supplements following training sessions. Subjects who ingested creatine were administered 15.75 g/day of creatine monohydrate for 5 days and an average of 5 g/day thereafter in 5-10 g/day doses. Fasting blood and 24-h urine samples were collected at 0, 1, 1.5, 4, 6, 10, 12, 17, and 21 months of training. A comprehensive quantitative clinical chemistry panel was determined on serum and whole blood samples (metabolic markers, muscle and liver enzymes, electrolytes, lipid profiles, hematological markers, and lymphocytes). In addition, urine samples were quantitatively and qualitative analyzed to assess clinical status and renal function. At the end of the study, subjects were categorized into groups that did not take creatine (n = 44) and subjects who took creatine for 0-6 months (mean 4.4 +/- 1.8 months, n = 12), 7-12 months (mean 9.3 +/- 2.0 months, n = 25), and 12-21 months (mean 19.3 +/- 2.4 months, n = 17). Baseline and the subjects' final blood and urine samples were analyzed by MANOVA and 2 x 2 repeated measures ANOVA univariate tests. MANOVA revealed no significant differences (p = 0.51) among groups in the 54-item panel of quantitative blood and urine markers assessed. Univariate analysis revealed no clinically significant interactions among groups in markers of clinical status. In addition, no apparent differences were observed among groups in the 15-item panel of qualitative urine markers. Results indicate that long-term creatine supplementation (up to 21-months) does not appear to adversely effect markers of health status in athletes undergoing intense training in comparison to athletes who do not take creatine.
Greenwood M, Kreider RB, Melton C, Rasmussen C, Lancaster S, Cantler E, Milnor P, Almada A. Greenwood M, et al. Mol Cell Biochem. 2003 Feb;244(1-2):83-8. Mol Cell Biochem. 2003. PMID: 12701814
Kreider RB. Kreider RB. Mol Cell Biochem. 2003 Feb;244(1-2):89-94. Mol Cell Biochem. 2003. PMID: 12701815 Review.
Cancela P, Ohanian C, Cuitiño E, Hackney AC. Cancela P, et al. Br J Sports Med. 2008 Sep;42(9):731-5. doi: 10.1136/bjsm.2007.030700. Br J Sports Med. 2008. PMID: 18780799 Clinical Trial.
Almeida D, Colombini A, Machado M. Almeida D, et al. J Sports Med Phys Fitness. 2020 Jul;60(7):1034-1039. doi: 10.23736/S0022-4707.20.10437-7. J Sports Med Phys Fitness. 2020. PMID: 32597619 Clinical Trial.
Benzi G, Ceci A. Benzi G, et al. J Sports Med Phys Fitness. 2001 Mar;41(1):1-10. J Sports Med Phys Fitness. 2001. PMID: 11317142 Review.
Warrier AA, Azua EN, Kasson LB, Allahabadi S, Khan ZA, Mameri ES, Swindell HW, Tokish JM, Chahla J. Warrier AA, et al. Sports Health. 2024 Sep-Oct;16(5):695-705. doi: 10.1177/19417381231197389. Epub 2023 Sep 9. Sports Health. 2024. PMID: 37688400 Free PMC article.
Cui N, Zhang W, Su F, Zhang Z, Qiao W, Sun Y, Yang B, Kuang H, Wang Q. Cui N, et al. Molecules. 2023 Aug 30;28(17):6352. doi: 10.3390/molecules28176352. Molecules. 2023. PMID: 37687178 Free PMC article.
Metzger GA, Minneci PM, Gehred A, Day A, Klingele KE. Metzger GA, et al. J Orthop. 2023 Mar 25;38:73-78. doi: 10.1016/j.jor.2023.03.010. eCollection 2023 Apr. J Orthop. 2023. PMID: 37008451 Free PMC article.
Longobardi I, Gualano B, Seguro AC, Roschel H. Longobardi I, et al. Nutrients. 2023 Mar 18;15(6):1466. doi: 10.3390/nu15061466. Nutrients. 2023. PMID: 36986197 Free PMC article. Review.
Casciola R, Leoni L, Cuffari B, Pecchini M, Menozzi R, Colecchia A, Ravaioli F. Casciola R, et al. Nutrients. 2023 Feb 8;15(4):863. doi: 10.3390/nu15040863. Nutrients. 2023. PMID: 36839220 Free PMC article. Review.