PURPOSE: The present study was conducted to examine the effects of acute medium-chain triglyceride (MCT) consumption on behavioral cognitive function during a task often linked to rapid decision making and reaction time in sport.
METHODS: Thirty recreationally active college students (M=19, F=11) aged 18-25 participated in this study, which consisted of two experimental days, in a double-blind, randomized-order, crossover design. During each laboratory visit, subjects consumed a fruit smoothie, mixed with an MCT supplement, consisting primarily of coconut oil, or a placebo (the same smoothie, without the supplement). Executive cognitive function testing (using a modified Flanker task) was performed two hours later. To prevent any latent effects of the MCT supplement, trials were separated by at least 72 hours. Dependent variables included accuracy and reaction time on the executive cognitive function task.
RESULTS: Paired-sample T-tests were conducted for Flanker task accuracy and reaction time. MCT consumption did not affect response accuracy (MMCT(SD)=91(11)%, MCON=93(8)%; p=0.36) or reaction time (MMCT(SD)=412(60)ms, MCON=417(53)ms; p=0.71). Further separating the data into sub-sections, including the interference scores between congruent and deviant response accuracies (MMCT(SD)=12(13)%, MCON=17(20)%; p=0.22), and the interference scores between congruent and deviant reaction times (MMCT(SD)=-36(37)ms, MCON=-46(39)ms; p=0.29), also did not yield any significant results.
CONCLUSIONS: Acute medium-chain triglyceride (coconut oil) consumption did not appear to benefit or harm executive cognitive function when taken up to two hours before a cognitive trial, beyond the effects associated with carbohydrate supplementation (in the form of a fruit smoothie), especially if consumption did not lead to gastrointestinal distress. This implies that physical activities relying on rapid decision making and reaction time are unlikely to be affected by a single bolus of MCTs. Future research should investigate potential supplementation effects over longer periods of time, or in clinical populations that may benefit from MCT consumption.