• The Protein Game Changed: GNC Pro Performance ® 100% Casein protein powder is packed with more slow-absorbing protein per serving, fewer calories, and improved taste with extra help from all-natural colors and flavors. • Sustained Muscle Fuel: Designed for a slow and steady release of amino acids, GNC Pro Performance 100% Casein delivers 25g of gluten-free, micellar casein protein for muscle recovery and strength.ˆ • Lean Muscle Mass and Recovery: GNC Pro Performance 100% Casein is a complete protein with 11g of naturally occurring essential amino acids that support the protein synthesis needed for recovery and building lean muscle mass.ˆ • Banned Substance Tested: Trusted by athletes around the world, our formula is third-party tested for purity and potency—along with a completely transparent label and a banned substance tested formula. • No Artificial Colors, No Artificial Flavors, No Added Sugar, Gluten Free, No Soy When used in conjunction with an exercise program. Informed Choice products are subject to a rigorous Anti-Doping program that includes protocols for testing & monitoring for over 285 compounds.