In recent years, mounting evidence from various studies has suggested that incorporating a variety of fruits and vegetables into one's diet can lead to a reduced risk of many lifestyle-related health conditions, including diabetes, obesity, heart disease, and overall mortality. A recent double-blind, parallel randomized controlled trial published in The American Journal of Clinical Nutrition explored the potential benefits of blueberries, with specific focus on their effects on cognitive function, cardiovascular health, and effect on gut microbiota in older individuals aged 65-80 years.

      Conducted by researchers from the King's College London Faculty of Life Sciences and Medicine in the United Kingdom, the study investigated the effects of freeze-dried wild blueberry (WBB) powder consumption on endothelial function, cognitive function, arterial stiffness, blood pressure, cerebral blood flow, gut microbiome, and blood parameters. The study enrolled 61 participants who were randomly assigned to either the WBB group, which consumed 26 g of WBB powder daily (containing 302 mg anthocyanins), or the placebo group, which received a matched placebo (containing 0 mg anthocyanins).

      The results of the study revealed several interesting findings. Participants in the WBB group showed a significant increase in flow-mediated dilation (FMD), which is a measure of endothelial function, indicating improved vascular health. Furthermore, 24-hour ambulatory systolic blood pressure was reduced by 0.86% (95% CI: 0.56, 1.17, P < 0.001) and -3.59 mmHg (95% CI: -6.95, -0.23, P = 0.037) in the WBB group compared to the placebo group. Additionally, the WBB group exhibited a considerable increase in total 24-hour urinary excretion of (poly) phenols, indicating higher intake and absorption of these beneficial compounds.

      In terms of cognitive function, the WBB group also showed enhanced immediate recall on the auditory verbal learning task and simultaneous accuracy on a task-switch task, suggesting potential improvements in executive functioning and episodic memory. However, no significant changes were observed in cerebral blood flow or gut microbiota composition.

      These findings highlighted the potential cognitive and cardiovascular benefits of blueberry consumption in older individuals. The study suggests that (poly)phenols present in blueberries may have a protective effect against cardiovascular disease and may also enhance cognitive function in older adults who are at risk of cognitive decline.

      The most interesting finding from the study is that the consumption of blue berries is effective for enhancing the episodic memory in older people who are at risk of cognitive decline. Further research is warranted to elucidate the underlying mechanisms and to explore the long-term effects of blueberry consumption on cognitive and cardiovascular health. Nevertheless, this study adds to the growing body of evidence on the potential benefits of consuming plant based diets especially in older adults.