The effect of anthocyanins and anthocyanin-rich foods on cognitive function: a meta-analysis of randomized controlled trials

The rising prevalence of cognitive disorders highlights the urgent need for effective prevention strategies and therapeutic interventions. While adherence to a balanced diet has been associated with a reduced risk of cognitive decline, emerging evidence underscores the potential role of plant-derived bioactive compounds, such as (poly)phenols, with anthocyanins receiving increasing attention. This meta-analysis aimed to evaluate the effect of anthocyanin-rich interventions on cognitive performance. A systematic search of randomized controlled trials (RCTs) assessing the effects of anthocyanin supplementation and cognitive outcomes identified 59 eligible studies. Overall, anthocyanin intervention significantly improved global cognition (standardized mean difference (SMD) = 0.46, 95% CI = 0.30 to 0.63, I2 = 0.0%) compared with controls. Domain-specific analyses further revealed significant benefits for visuospatial processing/reasoning and attention (SMD = 0.37, 95% CI = 0.18 to 0.55, I2 = 76.3%), processing and psychomotor speed (SMD = 0.19, 95% CI = 0.05 to 0.34, I2 = 64.0%), verbal speed and fluency (SMD = 0.21, 95% CI = 0.03 to 0.39, I2 = 30.5%), episodic memory (SMD = 0.30, 95% CI = 0.10 to 0.50, I2 = 75.9%), and working memory (SMD = 0.24, 95% CI = 0.12 to 0.36, I2 = 46.5%). Collectively, these findings suggest that anthocyanin supplementation may improve multiple cognitive domains. Although these results are promising, further well-designed RCTs are needed to validate these outcomes and consolidate the current evidence base.