I have only read that lactose intolerance causes bloating. However my only symptom is frequent small bowel movements which over a week or a month result in hemmorrhoids. It is only after strictly limiting my diet to no milk products at all (accept a little butter) that my symptom clear up. A day or two after consuming milk products again it comes back. I suspect I am both lactose and milk-protein intolerant. I avoid all breads with whey (most unlabeled "fresh" breads and donuts contain whey), all cheeses.. anything with milk products. However, I seem to get away with having a little butter (though I am still experimenting). It took me a couple of years to to link all this together. I have been happily tight-assed since.