Their natural color means they're loaded with vitamins and antioxidants. Stadler recommends blueberries, red raspberries, and dark cherries as ideal fruits, and says you can't miss with any of the dark, leafy vegetables like spinach, kale, and Swiss chard. You can have them all year because, when it comes to nutrients, frozen is just as good as fresh.
You can find trusted nutrition information in the Dietary Guidelines for Americans, which contain advice about what and how much to eat and which foods to avoid. Every 5 years, the U.S. Department of Agriculture (USDA) and U.S. Department of Health and Human Services use the latest nutrition research to develop these Guidelines that encourage people to eat healthier.