The Efficacy of Omega-3 Supplementation in Cognitive Function Improvement: A Systematic Review

Abstract

Background: Omega-3, composed mainly of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), has aroused great interest due to its neuroprotective properties. Thus, it is believed that these acids can play a protective role against cognitive decline. Objectives: Investigate the effectiveness of Omega-3 supplementation in cognitive function improvement in individuals with, or without, mild cognitive impairment (MCI). Design and Setting: Systematic review performed at a medical school in Brazil. Methods: A literature review in the MedLine database was conducted using the following descriptors: “Omega-3 Fatty Acids”, “Cognitive Function” and its variations according to MeSH. Only randomized controlled trials conducted in humans, published in English in the last 10 years were included. The PRISMA statement was used to improve this review. Results: Four randomized controlled trials with DHA and EPA supplementation were analyzed. Narendran R et al. (2012) suggested a significant improvement in the performance of working memory in the 3-back test (p = 0.04). Strike SC et al. (2016) found significant improvements in the VRM memory test (p = 0.029) and in the MOT task (p = 0.038). Stavrinou PS et al. (2020) found significant improvement in the ACE-R and MMSE cognitive tests (p < 0,001; p=0,011) in elderly people with MCI. Bo Y et al. (2017) concluded that the intervention group had a significant improvement in the total BCAT test score (p <0.0001). Conclusions: Omega-3 has shown potential effectiveness in cognitive function improvement, especially in elderly people with MCI. However, it is important to carry out further research in the area.