This article is about creatine and cognitive function. For information on creatine and athletic performance see Vegan Weightlifting: What Does the Science Say?
A 2017 study from Brazil examined the effect of creatine supplementation on brain creatine (Solis, 2017). Researchers gave 14 self-described vegetarian adults (4 vegans, 9 lacto-ovo vegetarians, 1 ovo vegetarian) and 17 omnivorous adults 0.3 g/kg of creatine for 7 days. The vegetarians had a much lower dietary intake of creatine than the omnivores (0.01 vs 1.73 g, respectively) but brain and muscle creatine content was not different between these groups prior to supplementation. Brain creatine was not affected by supplementation in either group although the vegetarians had a significant increase in muscle creatine compared to the omnivores. These results support other studies that suggest that, in healthy individuals, brain creatine content is relatively stable and not markedly affected by supplementation at the level used in this study. The authors conclude:
The findings herein presented also cast doubt on the ability of creatine supplementation to effectively increase brain creatine/PCr [phosphorylcreatine] content in healthy individuals, regardless of their…dietary patterns. At least, it is safe to conclude that the supplementation protocol employed in this study, which is able to promote muscle creatine/PCr loading, failed to produce any increase in brain PCr, indicating that higher-dose and/or longer-duration protocols must be developed to optimize brain creatine/PCr accumulation.
A 2013 study from Brazil compared the creatine content in a section of the brain, the posterior cingulate cortex, between vegetarians (6 women and 8 men) and omnivores (Yazigi, 2013). The posterior cingulate cortex was chosen because it is related to emotion formation and cognitive function (processing, learning and memory). Although the vegetarians ate much less creatine than the omnivores (.03 vs. 1.34 g, respectively), they had similar brain creatine levels (6.0 vs. 5.9 IU, respectively). The authors stated:
It has been shown previously that oral [creatine] intake can have beneficial effects on cognitive function in vegetarians rather than in omnivorous individuals, suggesting that the former may show some deficit in brain [creatine] content. However, the present study refutes this hypothesis, reinforcing previous experimental data suggesting that brain [creatine] content relies primarily on local endogenous synthesis rather than on [creatine] dietary intake.
The authors pointed out that these finding should not necessarily be extrapolated to other parts of the brain. They also say:
[A] few but not all studies have revealed a positive effect of [creatine] supplementation on cognition in individuals exposed to highly stressing conditions (e.g. sleep deprivation and exhausting exercise).
A 2010 study of 121 young women (71 of whom were vegetarian or vegan) had the subjects supplement with either 20 g of creatine per day (four doses of 5 g throughout the day) or placebo for five days (Benton, 2010). At baseline, the vegetarians had similar memory to the meat-eaters, but after supplementation, the vegetarians who supplemented with creatine had better memory than the meat-eaters in either group. This study found that vegetarians were more sensitive to supplementation with creatine than meat-eaters. There were only minor side effects reported by some of the subjects.
A 2003 study of 27 lacto-ovo vegetarian and 18 vegan college students found that supplementing with 5 g of creatine per day for six weeks increased their mental capacity (Rae, 2003). There was no omnivore group so it is not clear if the supplementation would have also worked for omnivores. But in other studies on omnivores:
- Six weeks of creatine supplementation of .03 g/kg body weight per day did not improve cognitive function in a group of young adult omnivores, but the amount of creatine was only about 1 to 1.5 g/day (Rawson, 2008).
- In elderly omnivores, four doses of 5 g of creatine per day for one or two weeks increased their cognitive function in some but not all measurements (McMorris, 2007).
If you plan to supplement with creatine based on this study, realize that it is not recommended to take 20 g of creatine past an initial loading phase, which is typically one week or less. After that, 5 g per day or less is recommended.
Benton, 2010. Benton D, Donohoe R. The influence of creatine supplementation on the cognitive functioning of vegetarians and omnivores. Br J Nutr. 2010 Dec 1:1-6. [Epub ahead of print] PMID: 21118604.
McMorris, 2007. McMorris T, Mielcarz G, Harris RC, Swain JP, Howard A. Creatine supplementation and cognitive performance in elderly individuals. Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2007 Sep;14(5):517-28. (Abstract)
Rae, 2003. Rae C, Digney AL, McEwan SR, Bates TC. Oral creatine monohydrate supplementation improves brain performance: a double-blind, placebo-controlled, cross-over trial. Proc Biol Sci. 2003 Oct 22;270(1529):2147-50.
Rawson, 2008. Rawson ES, Lieberman HR, Walsh TM, Zuber SM, Harhart JM, Matthews TC. Creatine supplementation does not improve cognitive function in young adults. Physiol Behav. 2008 Sep 3;95(1-2):130-4. Epub 2008 May 15.
Solis, 2017. Solis MY, Artioli GG, Otaduy MCG, Leite CDC, Arruda W, Veiga RR, Gualano B. Effect of age, diet, and tissue type on PCr response to creatine supplementation. J Appl Physiol (1985). 2017 Aug 1;123(2):407-414.
Yazigi, 2013. Yazigi Solis MY, de Salles Painelli V, Artioli GG, Roschel H, Otaduy MC, Gualano B. Brain creatine depletion in vegetarians? A cross-sectional 1H-magnetic resonance spectroscopy (1H-MRS) study. Br J Nutr. 2013 Nov 29:1-3.