Supplements can be in the form of ready-to-drink shakes, bars, bites, oats, and gels and powders, and come in a variety of flavors. What follows is a review of the scientific literature on the good, the bad ,and the ugly regarding protein supplements.upplements can be in the form of ready-to-drink shakes, bars, bites, oats, and gels and powders, and come in a variety of flavors. What follows is a review of the scientific literature on the good, the bad ,and the ugly regarding protein supplements.