Micellar Casein is a dairy protein, sourced from cows milk, which is more readily digested and absorbed than other types of casein due to its natural form. During digestion, Micellar Casein forms itself into clumps and in doing so requires extended periods of time to fully assimilate itself into the body. A popular product for building muscle over long periods of fasting (like sleep), Micellar Casein has been a staple supplement in many diets for years and is an excellent choice for athletes looking to maintain or build muscle.