You can therefore feel fitter when you use protein shakes than when you eat carbohydrate-rich meals. Protein shakes are available in sports food stores or in natural food stores. Please note: for a good result it is important to exercise during the diet. For example, fitness is an excellent way for your body to make optimal use of the proteins that you ingest. Proteins healthy? Proteins (proteins) are very important building materials for the body. We need proteins for strong bones, teeth, nails, healthy hair and to grow. Protein shakes are therefore very healthy.