For anyone that cares, here's some more fun facts about protein. I happened to notice that the primary protein used in this shake is alpha and beta caseins. I don't really know the difference between the two, but caseins are found in milk sources...at least humans and cows as far as I know. Caseins, after being injested, get broken down by your tummy into casomorphins (sp?). And these casomorphins can have euphoric and/or pain killing properties. I haven't looked deep into the research, but have heard that the effects can be comprable to opium or morphine. This would probably explain why folks will tell you to have a glass of warm milk before going to bed...or before you start cutting yourself to calm the beast that is within I guess.