Since I have cut out casein before bed I have had much better sleep. Whenever I do take it before bed I have to get up to piss constantly and just can't sleep as well. Even if I wait a full 4 hours after taking it to go to sleep I still have trouble sleeping. I think that the fasting you do when sleeping is much better than drinking a casein drink before bed. You just are not suppose to go to bed with a full stomach. I feel a lot better when I don't drink casein before bed, because of the better sleep I get. Now casein during the day is a different story....I would rather have a casein/whey mix durning the day or straight casein...