Creatine Side Effects

Creatine is involved in moving energy within the cells of skeletal muscles, the ones that most concern weight trainers and bodybuilders, and thus has become extremely popular as a supplement. There are so many users, and some using it to such a great extent, that safety issues will invariably come up. Does it have any side effects? Are there any known dangers, longterm or shorterm? We'll take a look at some of the scientific literature in this article, as well as some news stories, to see if we can figure out whether creatine has a dark side or not.

First, let's take a look at some news stories from a few years back that involved the death of a high school wrestler. At the time, it was highly discussed in the media that creatine was responsible. However, on closer examination, it was found that the wrestler was trying to make a certain weight class within a short period of time and went on an extreme weight loss blitz. The autopsy concluded kidney failure due to dehydration. Ultimately, creatine was not a factor in this case.

How about scientific studies specifically looking at its safety?

There are, in fact, several. One older study from 1999 was actually a review of earlier studies, attempting to extract a conclusion as to creatine's side effects and dangers. The study suggested that the most prominent side effect was weight gain from water retention, but went on to suggest that since creatine is also stored in the brain, heart, and testes, more studies should be performed to see if there are any effects on these organs.

A more recent study followed 18 basketball players during their season, while taking creatine supplements. Standard tests of clinical signs were performed on them, and no abnormalities in any capacity were detected. The study concluded that creatine causes no measurable ill effects.

Another study published in Military Medicine gave 35 members of the U.S. Army creatine supplementation or a placebo over the course of a week and while doing pushups. Again, they were closely monitored for any changes. At the conclusion of the study, there were again no measurable effects on blood pressure or weight. Interestingly, the researchers also did not measure any performance differences in the pushups between the creatine and placebo groups. One of the main advertised benefits of creatine is the ability to improve energy levels during short, intense bursts of exercise.

So it appears creatine is fairly safe, then? According to most reports and known evidence, there is only the potential for weight gain through water retention and not much else. Longterm effects are unknown, but the supplement has been on the market for a long time now and no anecdotal problems seem to have manifested themselves among users. Creatine is an acid and not a hormone, and so longterm effects are probably unlikely. We at SupplementZone recommend the use of creatine for weight training, but results are not guaranteed.


Michigan Daily, January 7, 1998

Clin J Sport Med 1999 Apr;9(2):62.

European Journal of Nutrition Volume 44, Number 4 / June, 2005, pp. 255-261

Military Medicine, Volume 172, Number 3, March 2007, pp. 312-317(6)

J Am Pharm Assoc (Wash). 1999 Nov-Dec;39(6):803-10; quiz 875-7