Chocolate
Sweeten your brain-boosting diet with the dark kind (at least 70% cocoa); it contains flavonoids, another class of antioxidants that some research links to brain health. Other flavonoid-rich foods include apples, red and purple grapes, red wine, onions, tea, and beer.
Eat it: Frequently, as part of a healthy total calorie intake. Up to half an ounce daily has also been shown to lower blood pressure.