and to meet their daily protein intake, but what sets whey protein apart?“Whey protein is the watery portion of milk that separates from the curds during the cheese-making process,” says , MS, director of coaching at , a nutrition coaching company. “Even though whey is derived from cows' milk, whey protein has a low lactose content and is easily digestible. It’s also a complete protein, providing all nine essential amino acids,” Werner says.