Casein Protein WHAT IS CASEIN? If you’re training seriously and looking to reach the next level with your workouts and recovery, you need to discover casein. This protein really stands out among protein supplements thanks to its composition and how quickly it's digested and absorbed. Indeed, casein is a slow-releasing protein found in milk, cheese, and whey. https://www.nationalnutrition.ca/protein-supplements/casein-protein.html #CaseinProtein