I personally have some stomach issues (IBS). I have learned that you can read all you want about your particular problem and read online diets , but it is all just knowing your body . I stay away from milk , and fast food because of the grease. I usually make sure to read the labels on food items before eating it because surprisingly  a lot of food contains milk or milk products. I suggest that with your stomach being sensitive you go see a doctor so that you will have a better idea of what you are dealing with and how to work around the issue. There are also medications over the counter or prescription that can help you in times that you simply cannot avoid eating foods that upset your condition (BBQs, Parties ...) . Just pay attention to what you are eating maybe make a journal and mark which foods are not working , and go from there . Good luck , I hope I was able to help you .

Alisa