Nutritional studies are notoriously difficult to perform with certainty. Nevertheless, each new study result can be compared to what we already know to gauge its worthiness. In this study, known dietary habits were sifted against tested cognitive ability. The participants with the slower decline were also the ones who ate the most berries, particularly blueberries and strawberries. The study also found the anthocyanidin and flavonoid (known to be valuable nutritional components of berries and other foods) content higher in the general food choices of the mentally sharper group.
What is particularly interesting is that berries are also among the least sugary fruits. Someone on a low carbohydrate diet (for weight loss, diabetes prevention, cancer prevention or general health reasons) is able to include a moderate daily serving of berries even when other fruits are excluded. And a high sugary diet is suspected as increasing the risk for cognitive decline.
So for general health considerations as well as keeping your brain sharp, enjoy a daily serving of blueberries and strawberries.