We love our hearts. But what are our brains -- chopped liver? Author Neal Barnard says how we eat can improve not just the function of our tickers, but also the longevity of our noggins. In his new book, Power Foods for the Brain (Grand Central, $27), he outlines his nutrition plan to stave off Alzheimer's and dementia. Here are some of his smart choices.Walnuts: Vitamin E can be a brain booster, Barnard says, noting a Dutch study that showed that people with the most in their diets cut their risk of Alzheimer's by 25 percent. The best sources are nuts and seeds.Blueberries: "None of these have any cholesterol," he says, waving at the produce display. And that's important for the brain because clogged-up arteries translate into reduced mental function. He's particularly fond of this antioxidant-rich fruit that has been shown to help with memory problems.Broccoli: In combination with vitamins B6 and B12 (which Barnard recommends taking supplements of), the folate in broccoli can eliminate homocysteine, a destructive molecule that messes with the heart and brain.Sweet potatoes: Barnard says they're a dietary staple in Okinawa, a place where people have been found to have exceptional brain function in old age.Wine: A glass or two a night has been shown to cut Alzheimer's risk significantly. In theory, red wine is the better choice, Barnard says, because the resveratrol it contains may be good for your heart. But when it comes to the brain, a glass of any alcohol appears to offer similar protection.