People who eat one 3-ounce serving of black beans a day decrease their risk of heart attack by 38 percent, according to a study in the Journal of Nutrition. And while other beans are also good for your heart, none can boost your brainpower like black beans. That’s because they’re full of anthocyanins, antioxidant compounds that have been shown to improve brain function. They’re also packed with superstar nutrients, including protein, healthy fats, folate, magnesium, B vitamins, potassium, and fiber.