If you want to buy protein bars, then you should know what to look for. I will provide a list of most popular proteins, the brands and some of their nutritional information. I am not going to talk about the nutritional information of the brand that is on the front of the packet. For that, you can search the internet. Here are some links to some popular protein bars. I will start with the brands that you should be searching for. 1. Whey Protein Protein is a basic building block of proteins. It contains all essential amino acids. You can find it at most health stores. 2. Whey Protein Isolate - It is the most common form of whey protein. The best whey protein is whey protein isolate, or whey protein concentrate. It is an amino acid-packed liquid protein that is high in protein but low in carbs. It has no lactose. 3. Whey Protein Isolate Isolates - These are the types of whey proteins that are available in liquid form. They have the exact same amino acid profile as whey protein concentrate. However, they have the advantage of being liquid. If you want the protein bars, you should choose the best one.