Creatine side effects: Fact or fiction?
Creatine has established itself as one of the most effective and
popular supplements available for people wanting to build muscle
and improve performance. However, there are concerns that creatine
is unsafe. Are the stories about creatine side effects that often
appear in the popular press based on fact or fiction?
Creatine is a very popular supplement. That's mainly because it
accelerates gains in muscle size and strength compared to exercise
alone. In a 12-week trial by Jeff Volek and a research team from
Pennsylvania State University, creatine users ended up stronger
in both the squat and bench press compared with subjects using a
"dummy" supplement [9]. They also gained twice as much
muscle.
Creatine side effects
There are claims that creatine users are more susceptible to cramps,
muscle spasms, and even pulled muscles. However, in a three-year
study designed to find out whether these creatine side effects really
do exist, creatine had no effect on the incidence of injury or cramping
in a group of American footballers [2].
Research published in the journal Medicine and Science in Sports
and Exercise shows similar results [3]. In a group of 26 athletes
using creatine for up to four years, there was no difference in
the reported incidence of muscle cramp or injury compared with athletes
not using creatine.
A more recent study, published in the September 2004 issue of the
International Journal of Sports Medicine, also shows that
creatine side effects are rare [11].
A group of 175 subjects received either 10 grams of creatine or
placebo daily for an average period of 310 days. Diarrhea and nausea
did cause three subjects to stop using creatine. But there were
no other significant differences between the groups.
Researchers from Truman State University also report that long-term
creatine use appears to be safe [7].
Twenty-three members of an NCAA Division II American football team
were divided into a creatine group and a control group who took
no supplements.
Subjects in the creatine group averaged 14 grams of creatine a
day for three years. However, the researchers could find no detrimental
effects on either kidney or liver function.
When I started using creatine in 1996, I can still remember one
occasion when I suffered from extremely painful muscle cramps. After
teaching a 45-minute exercise class in a hot and humid swimming
pool hall, the first thing I should have done was get something
to drink. But I didn't. Instead, I went straight into the office
and sat down to read a newspaper.
Suddenly, the back of my left thigh started to cramp up. So, I
straightened my leg to try to ease the pain. Then, the front of
my thigh started to cramp as well. I didn't know what to do. I couldn't
bend or straighten my leg so I just sat there hoping the
pain would go away.
Of course, I have no idea whether or not creatine contributed to
the problem. Scientists aren't really sure what causes cramp in
the first place. But up until then, I'd never experienced such painful
cramps in the front and back of my thigh at the same time.
Now, I always make sure to carry a bottle of water with me when
I go to the gym.
Most people aren't aware that creatine has protective effects in
heart, muscle and neurological diseases. In fact, several months
of creatine supplementation in men and women with borderline high
cholesterol levels reduces very-low-density lipoprotein levels (the
so-called "bad" cholesterol) by almost one-third [1].
Similar findings are reported in the journal Metabolism.
Twenty-eight days of creatine supplementation and resistance exercise
lowered total cholesterol levels to a greater extent than resistance
exercise alone [10].
The bottom line
Carefully controlled studies over the short- (five days), medium-
(nine weeks) and long-term (up to five years) have yet to demonstrate
that creatine supplementation has any adverse effects on blood pressure,
kidney or liver function in healthy individuals [3, 5, 6, 7, 8].
Of course, an absence of evidence is not evidence of absence. The
fact that large trials have yet to find any serious creatine side
effects doesn't mean that none exist. There are isolated case reports
of individuals suffering from kidney problems after using creatine
[4]. Anyone with existing liver or kidney problems, or those predisposed
to such ailments, should seek medical advice before using creatine.
About The Author
Christian
Finn holds a masters degree in exercise science, is a certified
personal trainer and a regular contributor to Men's Health, Men's
Fitness and other popular fitness magazines.
If you're stuck
in a rut with your current exercise and diet plan... fed up with
only losing a pound here and there... or still skinny after months
(or even years) of trying to build muscle and gain weight... click here now for instant access to his step-by-step muscle-building and fat-burning workout routines.
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References
1. Earnest, C., Almada, A., & Mitchell, T. (1996). High-performance
capillary electrophoresis-pure creatine monohydrate reduces blood
lipids in men and women. Clinical
Science, 91, 113-118
2. Greenwood, M., Kreider, R.B., Melton, C., Rasmussen, C., Lancaster,
S., Cantler, E., Milnor, P., & Almada, A. (2003). Creatine supplementation
during college football training does not increase the incidence
of cramping or injury. Molecular
and Cellular Biochemistry, 244, 83-88
3. Schilling, B.K., Stone, M.H., Utter, A., Kearney, J.T., Johnson,
M., Coglianese, R., Smith, L., O'Bryant, H.S., Fry, A.C., Starks,
M., Keith, R., & Stone, M.E. (2001). Creatine supplementation
and health variables: a retrospective study. Medicine
and Science in Sports and Exercise, 33, 183-188
4. Pritchard, N.R., & Kalra, P.A. (1998). Renal dysfunction
accompanying oral creatine supplements. Lancet,
351, 1252-1253
5. Poortmans, J.R., & Francaux, M. (2000). Adverse effects of
creatine supplementation: fact or fiction? Sports
Medicine, 30, 155-170
6. Kreider, R.B., Melton, C., Rasmussen, C.J., Greenwood, M., Lancaster,
S., Cantler, E.C., Milnor, P., & Almada, A.L. (2003). Long-term
creatine supplementation does not significantly affect clinical
markers of health in athletes. Molecular
and Cellular Biochemistry, 244, 95-104
7. Mayhew, D.L., Mayhew, J.L., & Ware, J.S. (2002). Effects
of long-term creatine supplementation on liver and kidney functions
in American college football players. International
Journal of Sport Nutrition and Exercise Metabolism, 12,
453-460
8. Vannas-Sulonen, K., Sipila, I., Vannas, A., Simell, O., &
Rapola, J. (1985). Gyrate atrophy of the chloroid and retina: a
five year follow-up of creatine supplementation. Opthalmology,
91, 1719-1727
9. Volek, J.S., Duncan, N.D., Mazzetti, S.A., Staron, R.S., Putukian,
M., Gomez, A.L, Pearson, D.R, Fink, W.J., & Kraemer WJ. (1999).
Performance and muscle fiber adaptations to creatine supplementation
and heavy resistance training. Medicine
and Science in Sports and Exercise, 31, 1147-1156
10. Arciero, P.J., Hannibal, N.S. 3rd, Nindl, B.C., Gentile, C.L.,
Hamed, J., & Vukovich, M.D. (2001). Comparison of creatine ingestion
and resistance training on energy expenditure and limb blood flow.
Metabolism,
50, 1429-1434
11. Groeneveld, G.J., Beijer, C., Veldink, J.H., Kalmijn, S., Wokke,
J.H.J., & van den Berg, L.H. (2004). Few adverse effects of
long-term creatine supplementation in a placebo-controlled trial.
International
Journal of Sports Medicine, 25
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