This high-quality protein is low in carbs and low in sugar. The main source of protein is Whey Protein Concentrate and Whey protein isolate making it perfect for a low-calorie diet. Spartan 100% Whey Pro Series is an excellent source of all the essential amino acids and is extremely rich in the Branched Chain Amino Acids (BCAAs) Leucine, Isoleucine, and Valine.