<<Disclaimer: Verify this information before applying it to your situation.>> Re travel on ships. I had a good experience on Holland American Lines to Alaska. I told them in advance of my problem. I found there were lots of salads, plain meats and fish, fresh fruit and veggies and I avoided all breads cereals etc. which I do at home. I don't tolerate rice, corn , soy and have some problems with dairy as well. I found I had no problems on the trip and even lost a few pounds which I had wanted to do. Wheat and other gluten products make me gain weight and make me constipated. In fact having food available all day long prepared, especially the fresh fruit and veggies made things really easy for me. I just accept that bread, cereals and cake of any sort are not part of my life. I don't say I like it, I just force myself to accept it. After all there are much worse things in life.