Helps build and maintain muscle Supports endurance and recovery Hydrolyzed & ultra-filtered whey protein isolate Fast-digesting Rich Vanilla flavor. Support your muscle building endurance and recovery goals with GOLD STANDARD 100% ISOLATE by Optimum Nutrition. This Rich Vanilla shake mix delivers 25g of the highest-quality hydrolyzed whey protein isolate—containing 0g of fat only 1g of carbohydrates and more than 80% of pure protein per serving. Whey protein isolate (WPI) has the highest concentration of protein and BCAAs while having less carbs cholesterol and fat compared to other whey proteins. WPI is also low in lactose and easy on your digestive tract. Hydrolyzed whey protein isolate (HWPI) is whey protein isolate that has been broken down into smaller chains of amino acids called peptides. Peptides are easier to digest allowing for faster absorption into the bloodstream. Branched-chain amino acids (BCAAs) include leucine isoleucine and valine. They support muscle growth and reduce muscle fatigue.