Aug. 15, 2003 -- Supplementation with 5 g creatine daily improved working memory and intelligence, both tasks which require speed of processing, according to the results of a double-blind, placebo-controlled trial published in the Oct. 22 issue of the Proceedings of the Royal Society: Biological Sciences.



"The level of creatine supplementation chosen was 5 g per day as this is a level that has previously been shown to increase brain creatine levels. This level is comparable to that taken to boost sports fitness," lead author Caroline Rae, from the University of Sydney in Australia, says in a news release. "Vegetarians or vegans were chosen for the study as carnivores and omnivores obtain a variable level of creatine depending on the amount and type of meat they eat — although to reach the level of supplementation in this experiment would involve eating around 2 kg of meat a day!"

Previous studies, as well as anecdotal reports, suggest that creatine supplementation can increase sports performance and could potentially be useful in treating neurological, neuromuscular and atherosclerotic disease. Brain creatine levels have been shown to correlate with improved recognition memory and with reduced mental fatigue.

"We know that creatine plays a pivotal role in maintaining energy levels in the brain," says Dr. Rae. "So it was a reasonable hypothesis that supplementing a diet with creatine could assist brain function."

In a cross-over design trial, 45 young adult vegetarians were randomized to receive creatine supplementation, 5 g daily, or placebo for six weeks, followed by a six week washout period and then six weeks of the alternate treatment.

Creatine supplementation had a positive effect ( P < .0001) compared with placebo on both working memory, as measured with the backward digit span test, and on intelligence, as measured with Ravens Advanced Progressive Matrices.

"The results were clear with both our experimental groups and in both test scenarios: creatine supplementation gave a significant measurable boost to brain power," Dr. Rae says. "These findings underline a dynamic and significant role of brain energy capacity in influencing brain performance. Increasing the energy available for computation increases the power of the brain and this is reflected directly in improved general ability."

Long-term supplementation with creatine may have potential adverse effects on glucose homeostasis, as well as on body odor. "To be frank taking the supplement can make you a considerably less 'fragrant' person," says Dr. Rae. "However, creatine supplementation may be of use to those requiring boosted mental performance in the short term — for example, university students."

The Australian National Health and Medical Research Council supported this study.

Proc Royal Soc. 2003

Reviewed by Gary D. Vogin, MD