Eating about three ounces of pecans daily can cut your risk of heart disease by 30 percent or more, according to the massive Harvard Nurses Health Study. “Pecans are loaded with monounsaturated fatty acids -- a healthy kind of fat that nourishes and strengthens artery walls, helping to prevent plaque buildup,” explains Frank Hu, Ph.D., a professor of nutrition at the Harvard School of Public Health. Not a pecan fan? Eating three ounces of your favorite nut every day -- or two tablespoons of natural peanut butter (meaning no sugar added!) -- will give you the same great protection.