But not all chocolate is created equal. Milk chocolate has too little cocoa to provide benefits, and white chocolate -- which is not really chocolate -- has no cocoa at all. "Cocoa," Nolan says, "is where you are getting the nutrition and the brainpower."
Stick to dark, bittersweet chocolate and no more than a few squares a day, about half an ounce. Or stir a teaspoon of cocoa powder into your Greek yogurt. Avoid alkalized or Dutch processed cocoa, which has fewer antioxidants than regular cocoa.
Dark green vegetables. Spinach, asparagus, broccoli, and Brussels sprouts all provide folate, which Gomez-Pinilla says appears crucial to brain function. Eat a good mix of veggies rather than favoring just one or two, so you get a mix of nutrients, he adds.
Beans. Bring on the burritos! Beans supply high-quality protein, magnesium, and B vitamins, all of which help your brain work. Because beans also have lots of fiber and complex carbohydrates, you'll digest them slowly and benefit from them over the course of the day. Nolan says that, across the board, all beans provide about the same amounts of protein and fiber. They are also good sources of omega-3s and antioxidants, particularly kidney beans. Try to eat one-half to two-thirds cup of beans every day, Nolan recommends.
Coffee. Caffeinated coffee gives you a dose of early morning energy, and in small doses, it can help you concentrate, Nolan says. The key word here is "small." Stick to 8-ounce cups instead of grande-size portions to avoid caffeine jitters -- and extra calories, if you're a latte, mocha, or cappuccino drinker.
Don't like coffee? Do what Gomez-Pinilla does and choose green tea, which has many of the same health benefits.
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