True, some nuts are more than 80 percent fat, but these foods are also the best plant sources of heart healthy Omega 3 fatty acids. Nutrition experts recommend one ounce of nuts at least five times a week to lower risk of cardiovascular disease and type 2 diabetes. In addition to healthy fats and protein, nuts provide vitamin E, fiber, and cholesterol reducing plant sterols. But to a growing number of children and adults, nuts can actually be dangerous. Tree nuts have become the most common and fastest growing food allergens in the population today.