Apples
Here's a new reason to munch on an apple a day: Apples are a leading source of quercetin, an antioxidant plant chemical that keeps your mental juices flowing by protecting your brain cells.
According to researchers at Cornell University, quercetin defends your brain cells from free radical attacks which can damage the outer lining of delicate neurons and eventually lead to cognitive decline.
To get the most quercetin bang for your buck, be sure to eat your apples with their skins on since that's where you'll find most of their quercetin.