I gave up protein shakes months ago since I eat well enough to not worry about getting the proper nutritional values in my body. If you are in a pinch it is something of convenience instead of eating some crappy fast food then a protein shake will do. Supplements are that they supplement your diet and protein shakes are no substitutes for food especially when they contain a bunch of chemicals and artificial sweetners that can create havoc on your neural system. Also a lot of proteins are containing soy for added taste and studies have shown that high soy consumption can lead to elevated estrogen levels in men. No study is saying that eating a steak is raising your estrogen levels