Background:
Gradual deterioration of cognitive ability is linked to age and various risk factors such as overweight, blood pressure, and dietary intake. Anthocyanins are a polyphenol subgroup, mainly found in berry fruits. Multiple studies in both children and elderly have observed favorable effects of anthocyanin intake on cognitive performance. However, the effect of the anthocyanin-rich berry fruit Aronia melanocarpa on cognitive performance remains unexplored. Therefore, the goal of this study was to assess the effect of 24 weeks of Aronia melanocarpa extract (AME) supplementation on cognition, mood, and vascular function in a healthy, middle-aged, overweight population.

Methods:
A randomized double-blind placebo controlled parallel study was designed and included 101 participants that consumed either 90 mg AME, 150 mg AME, or placebo for 24 weeks. Cognitive measures consisted of the grooved pegboard test (psychomotor speed), the number cross-out test (attention), and the Stroop test (cognitive flexibility). In addition, mood was evaluated with a visual analogue scale. Lastly, serum brain-derived neurotrophic factor (BDNF) and vascular function (blood pressure and carotid ultrasounds) were assessed as potential mechanisms involved in cognitive performance

Results:
90 mg AME supplementation resulted in an improved score on the grooved pegboard test (psychomotor speed) compared to placebo (change = -3,37; p = 0.009). No differences were observed for the other cognitive tests, mood, or BDNF. Furthermore, supplementation with 150 mg AME decreased brachial diastolic blood pressure compared to 90 mg AME (change = 2.44; p = 0.011), but not compared to placebo. The other parameters for vascular function were unaffected.

Conclusion:
Supplementation with AME demonstrated an indication of a protective effect on both cognitive ability and blood pressure in individuals at risk of cognitive decline. Further research is crucial to determine associated mechanisms.