I have several questions, trying to figure out for myself why people may be reacting to various foods, including dairy, and if any of my reactions are due to dairy or not. 1. I have heard that there are basically 3 things people may be reacting to in dairies: lactose, casein, whey. Some people may be sensitive to some, but not others. E.g. sensitive to casein, but not whey. Is this true? 2. If the reaction is to proteins - casein, whey - can one take protein digesting enzymes to break them up? I am already taking bromelain, there are plenty others out there as well. Or is the reaction to specific chains of aminos that are found in milk proteins and would not be broken down by these enzymes. 3. If the reaction is to casein (or even whey) why is there reaction to other dairies, such as yogurt. I thought that bacteria in yogurt use the milk proteins to make the proteins they need, therefore the only milk proteins found in yogurt would be 'residual' proteins, not yet digested by the bacteria. Is this residual amount of milk proteins responsible for the reactions? 4.a. Is it possible that reaction to milk proteins really happens due to other reasons. For example, gluten, yeast overgrowth, or other problems causing 'leaky gut syndrome' or similar problems. So your body now starts absorbing incompletely digested milk proteins and then starts developing antibodies to them. Has anybody had these kinds of problems? And if yes, has milk intolerance improved when those problems were taken care of? 4.b. The reason I am thinking of this is that if the body is developing antibodies to milk proteins they must be getting into blood steam. The body does not normally develop antibodies to things still in the gut, as that will be broken down and there is no reason to 'waste' immune system efforts on it. If milk particles (proteins, lactose, whatever) are getting into blood stream then the problem is with the 'leaky gut'. Does this make sense? 5. Could the problems with milk (and eggs, etc. for that matter) be due to hormones, antibiotics, pesticides, etc that go into cows and end up in milk? Anybody switched to organic dairies (or eggs, etc.) and found their symptoms improve? 6. I have seen a lot of references to Paleolithic diets, eating only what could be picked in nature/killed with a stick. Dairies are usually excluded from that list on the basis that neanderthals did not raise cows. But they were still breast fed as infants. Does anyone know why these diets exclude milk if it's a natural part of one's life early on? How is human milk different from cows, goats, etc.? 7. I remember seeing that casein is similar to another protein in another food that people are sensitive to, but can't remember which one. Is that gluten? Anybody out there remembers this?