Variations to Try . Protein-packed: Use strained (Greek-style) yogurt, which is naturally high in protein, and consider adding a scoop of your favorite protein powder, a handful of nuts or a tablespoon of nut or seed butter.These additions will add calories, but will make it more satisfying. A tropical twist: For a tropical-tasting smoothie, use a blend of frozen pineapple, mango and banana as ...