Cytosport's Muscle Milk Light is what a lot of Muscle Milk fans had been asking for: Take the same high-protein, nutritionally-fortified Muscle Milk formula, and reduce the calories and fat. Muscle Milk Light, like Muscle Milk, is also patterned after the ideal, anabolic food, human milk, with highly bioavailable proteins, vitamins and minerals. So, like Muscle Milk, it's a great Meal Replacement powder for anyone trying to pack on lean body mass. Which Muscle Milk is right for you? Muscle Milk Original is probably better for those trying to gain overall weight, Muscle Milk Light is a better choice for those trying to lean up and gain lean mass only.