Do you avoid Carrageenan? If you have IBS or food sensitivities and still have GI distress, it might be that you don't tolerate the food additive carrageenan commonly found in dairy and non-dairy products. We are learning carrageenan, made form seaweed, may not actually be good for us.
Here's what Dr. Weil says about it:
Carrageenan is a common food additive that is extracted from a red seaweed, Chondrus crispus, which is popularly known as Irish moss. Carrageenan, which has no nutritional value, has been used as a thickener and emulsifier to improve the texture of ice cream, yogurt, cottage cheese, soy milk and other processed foods. When I first wrote about carrageenan on this site 10 years ago, I reported that some animal studies had linked degraded forms of it (the type not used in food) to ulcerations and cancers of the gastrointestinal tract. But around that time, a prominent researcher in the field, Joanne K. Tobacman, M.D., now associate professor of clinical medicine at the University of Illinois College of Medicine, conducted studies linking undegraded carrageenan - the type that is widely used in foods - with malignancies and other stomach problems. (Degraded and undegraded carrageenan differ by molecular weight with undegraded carrageenan having the higher weight.)
Take a look at this list (or better yet, READ ingredient lists on all dairy and non-dairy products) from the Cornucopia Institute: