I've recently been suspecting I have lactose intolerance. For a long time I would have gas pain followed by diarrhea 1-2 hours after eating some meals. I never could tell what would bring it on...very embassing when out with friends. Lately I've been noticing I can find some kind of dairy product earlier in the day and then maybe a cream sauce or cheese in the meal. It doesn't seem to happen every time I have dairy but when it does happen there usually was 2 or more dairy foods that day.