What Is Casein Protein Powder? Casein protein powder is a protein derived from milk. Milk contains two types of protein: casein and whey. Whey protein is fast digesting, which means it is absorbed extremely quickly and is great for taking immediately after exercise. Casein protein is slow-digesting, which means it releases amino acids slowly instead of quickly like whey. Casein protein is often taken before periods of rest and sleep. Casein Protein Powder Benefits † Casein protein powder contains BCAAs and may assist in the recovery of muscles after strenuous physical activity. Supplementation of casein protein may also help with general development of lean muscle mass at a faster rate. In addition to its high protein content, one serving of casein contains almost half of the daily recommended value of calcium, which may promote healthy bones. Slow absorption rate Loaded with essential amino acids Help with muscle recovery Contribute to muscle growth Help maintain healthy weight in already healthy individuals