Before anyone gets the wrong idea, one of the above is optional, and the other is not. Most people can get by without supplements, even if they have to modify their diet. However, supplements aren’t meant to replace eating normal food, preferably as unrefined and whole as possible. Under medical supervision, supplements, similar to protein shakes, are sometimes used to replace a normal diet. For instance, this can be observed in weight loss through a “protein sparing fast,” or in cases where a patient can’t ingest sufficient solid calories. Even so, this is still considered to be a temporary measure.