Blueberry consumption significantly improves two-back test accuracy, suggesting potential cognitive benefits.
A comprehensive search was conducted in April 2021 for relevant clinical trials on blueberry supplementation and its effects on cognitive performance and mood. The search was conducted through PubMed/Medline, Scopus, Embase, and Google Scholar, and the random effect size was used to estimate the pooled effect size. Cochrane Q test and I-squared tests were used to evaluate heterogeneity between studies, and a subgroup analysis was done to detect potential sources of such heterogeneity. Fourteen randomized trials were included in the quantitative analysis, and six were pooled for statistical analysis.
Blueberry intervention did not produce any significant impact on mood state score, attention task reaction time, or on the percentages of attention task accuracy. Similarly, it had no significant effect on one-back test accuracy. However, a noticeable positive effect was detected in two-back test accuracy, indicating possible cognitive benefits associated with blueberry consumption.
