Vasil William Dhimitri/
Creatine is widely recognized as a substance that helps muscles generate energy during
straining tasks. Although it is generally assumed that creatine is only relevant to athletes and
bodybuilders, the scientific community is currently researching another creatine application – specifically, concerning the brain and cognitive function.
As creatine anaerobically restores ATP and plays a role in the brain’s CK/PCr system, its supplementation should theoretically improve cognitive function and be helpful to vegetarian, oxygen-deprived or neurodegenerative, and sleep-deprived individuals. To get some answers in practice, I investigate here whether creatine enhances cognitive function and to what extent, if any, it offsets impairments in the affected individuals.
First and foremost, creatine improves intelligence and memory in young, vegetarian adults. Rae,
C. et al.’s study provides convincing data demonstrating creatine’s ability to rapidly resynthesize
ATP when local areas in the CNS activate due to straining tasks1. In this experiment 45 young,
vegetarian adults came in four times at six-week intervals, where they took blood and cognitive
tests, followed by the administration of 5g creatine or placebo tablets. Between weeks 6 and 12, the second experimental period, a supplement “wash-out” was implemented1. The two tasks subjects fulfilled were Raven’s Advanced Progressive Matrices (RAPMs) and the Weschler Auditory backward digit span (BDS)1. Collectively, these metrics validated (p<0.0001) that creatine improves intelligence and memory in young, vegetarian adults. In terms of the RAPMs dataset, creatine-supplemented vegetarians performed better by 1.5 units at the end of the first experimental period (week 6) and 5.5 units at the end of the third experimental period (week 18). In addition, the mean RAPMs score concerning the placebo group was 9.7 compared to the 13.7 of its counterpart1. On the other hand, the BDS scores performed similarly, with the creatine group having a one-unit and a two-unit advantage at the end of the first and third experimental periods, respectively. Under the placebo group, the mean BDS score was 7.05 compared to 8.5 under the supplementation group1. Overall, the study concludes that because creatine supplementation scores were higher all round, creatine improves intelligence and memory
in vegetarians as a direct result of increased ATP rates in neuronal mitochondria.
A second study by Turner, C.E. et al. on the impacts of creatine on cognitive performance during
oxygen deprivation claims that creatine supplementation counteracts the effects of oxygen loss and chronic energy disruption in young adult brains. Researchers modelled these disruptions with acute oxygen deprivation conditions in 15 young adults. The subjects took creatine or placebo treatments for a week straight to increase brain creatine content, followed by placement in hypoxia-induced environments for 90 minutes, in which they took seven tests, classified upon four neurocognitive domains: complex attention, executive function, cognitive flexibility and neurocognitive index2. Generally, creatine supplementation improved cognitive performance2. In complex attention, the creatine group had a standard score of 20 units higher than the placebo group. Regarding executive function, that difference was 10 units. Once again, in cognitive flexibility, creatine supplementation performed better by 12 units. Most importantly, the neurocognitive index was better by 7 units in the creatine group. Another metric, accounted for the sum of motor-evoked potentials in hypoxic conditions2. The creatine group scored 1.1, and the hypoxia group, 0.2. Simply put, creatine availability in the brain corrects cognitive deficiencies in straining environments, as shown by a 21% difference between the groups2. This supports the argument that creatine supplementation enhances cognitive performance because it prevents oxidative stress, ensures smooth synaptic transmission and sustains membrane potentials.
Mood tests relating to fatigue and vigour favoured the creatine group by twice as much as the placebo group in the 12h and 24h intervals. When combined, the results assert that creatine supplementation aids in improving psychomotor function during sleep-deprivation3.
While the former studies provide strong evidence that creatine supplementation positively
affects cognitive function, the latter three studies show little to no effect. To begin with, Rawson
E.S. et al.’s findings claim that creatine supplementation does not significantly impact young
adults4. While Rawson E.S. et al. state that creatine supplements increase brain creatine content,
they disagree with the notion that cognitive performance is improved4. Twenty-two non-vegetarian young adults were considered and given 0.03g of creatine or placebo per kilogram of body weight for 6 weeks. Researchers then tested reaction time, code substitution, logical reasoning, mathematics and memory.
Measured in ms or throughput, the comprehensive dataset results yielded p values greater than
0.05, certifying that for all tests, there is not a single valuable group, time or group-by-time
interaction, or any statistically significant difference4. While the scope of this essay cannot analyse every data element in Rawson E.S. et al.’s table, the throughput for mathematical processing is one of many cases where no statistically significant relationship exists. For example, the creatine group’s mean throughput before treatment is 25.4±7.6 and 26.3±7.3. For the placebo group before treatment, the mean throughput is 24.1±5.5 and after, 24.7±5.4. Changes like these, in all test categories, bear very little significance and therefore support the counterargument that creatine does not influence cognitive function in any way, shape or form.
Another study that presents similar findings is Benton, D. & Donohoe, R.’s comparative
experiment on the impacts of creatine in vegetarian and omnivorous populations5. The methodology involved several young vegetarian and omnivore adults, who consumed 5g creatine or placebo tablets for 5 days followed by completion of cognitive tests like word recall, reaction time, vigilance and verbal fluency. For word recall, creatine consumption led to poorer memory5. Pre-supplement to post-supplement, the vegetarian population’s mean words recalled dropped from 14 to 13.
Pre-supplement to post-supplement, the omnivore population’s mean words recalled declined from 14 to 11. For reaction times, neither decision nor movement times were affected by creatine to a significant degree in both vegetarians and omnivores5. The same applies to vigilance, and word fluency, where the graphs presented show almost no deviation between both groups before and after taking the creatine or placebo tablets5. In summary, Benton, D. and Donohoe, R. ‘s findings demonstrate that memory did not differ before at baseline depending on dietary style and after when the experiment was concluded. Put differently, while creatine does not influence memory in any shape or form, vegetarians are more sensitive to it, leading researchers to believe that the impacts may be indirect.
Finally, the last study of concern that highlights creatine not affecting cognitive function is by
Alves, C.R.R. et al., who observe several parameters related to creatine supplementation in older
women6. Ageing is a phenomenon in which cognitive performance and emotional decay occur, so it would make sense to suggest that creatine supplementation could potentially improve mental health. However, this is not the case at the end of Alves, C.R.R. et al. ‘s methodology, which involves 56 women assessed at 12 and 24 weeks after consuming 4x5g creatine or placebo doses. The tests were mental state, Stroop, trail making, digit span, delay recall and Geriatric Depression.
As is the case in Rawson E.S. et al.’s data tables, all test results had p-values above 0.05,
nullifying any potential for statistical significance concerning creatine supplementation6. Among the various tests and examples available, a perfect case of creatine’s lack of effect would be in the
“colour words” section of the Stroop test, in which the pre-supplement score was 32.7±10.8, and the post-supplement score was 32.8±11.1. The Geriatric Depression Scale for those who were
supplemented with creatine yielded similar or lower scores at 12 and 24 weeks6. Therefore, this
study confidently asserts that in healthy older individuals, the impacts of creatine are slim to none.
In conclusion, both sides present convincing arguments for creatine affecting and not affecting
cognitive function. Either side has performed detailed double-blind, randomised,
placebo-controlled studies. However, the “yes” side offers a more wholesome insight on creatine’s biochemical functions – and emphasises this by conducting experiments on vegetarians, oxygen-deprived and sleep-deprived individuals. The “no” side observes only healthy, omnivorous individuals, in which the effects are too marginal or preliminary to be considered significant. In admitting that their experiments lack the quantity of supplement given, they set themselves short because the results yielded for healthy people in normal conditions are extremely small and the changes, compared to the baseline and the opposing side, are pretty invisible.
References List
1. Rae, C., Digney, A.L., McEwan, S.R. & Bates, T.C. Oral creatine monohydrate supplementation improves brain performance: a double–blind, placebo–controlled, cross–over trial. Proc. R. Soc. Lond. 270, 2147-2150 (2003).
2. Turner, C.E., Byblow, W.D. & Gant, N. Creatine supplementation enhances corticomotor
excitability and cognitive performance during oxygen deprivation. J. Neurosci. 35, 1773-1780
(2014).
3. McMorris, T. et al. Effect of creatine supplementation and sleep deprivation, with mild exercise, on cognitive and psychomotor performance, mood state, and plasma concentrations of
catecholamines and cortisol. J. Psychopharmacol. 185, 93-103 (2006).
4. Rawson, E.S. et al. Creatine supplementation does not improve cognitive function in young
adults. Physiol. Behav. 95, 130-134 (2008).
5. Benton, D. & Donohoe, R. The influence of creatine supplementation on the cognitive functioning of vegetarians and omnivores. Br. J. Nutr. 105, 1100-1105 (2011).
6. Alves, C.R.R. et al. Creatine supplementation associated or not with strength training upon
emotional and cognitive measures in older women: a randomised double-blind study. Plos One. 8, 1-10 (2013).
Autori Vasil William Dhimitri është student i vitit të katërt në Universitetin e Torontos, i specializuar në bioteknologji, biologji dhe kimi. Ai është nderuar me disa nga çmimet dhe bursat më të larta akademike në Kanada. Përveç arritjeve në studime, Vasili ka punuar si kërkues shkencor në University of Toronto Mississauga dhe si praktikant në disa institucione shëndetësore. Ai ka kontribuar gjithashtu si asistent pedagog dhe mentor për studentët e rinj, duke ndërthurur shkencën me edukimin dhe praktikën.