Hi addyp. It's different for everyone, and it's different depending on where the disease is doing it's dirty work. Some say low residue, low fiber diet (which means soft breads, pastas, non-spicy, low fiber foods) is the way to go as these foods are easier to digest. If you know he is not sensitive to flour/sugar that should be fine. However, many people are very sensitive to flour and sugar as triggers and they trigger and make flares worse. In which case, lean protein and natural carbs (potatoes, rice, etc)., might be the better way to go. It's all trial and error, so pay close attention to what he eats and how it impacts his symptoms. Hopefully this helps. I eat a ton of fish, chicken and eggs of all varieties when I am flaring. And for snacks it's banana's, nuts, and hard cheeses. Oh and I'm sure baby food would be a good alternative for a snack as well. Just some suggestions and I hope you can figure it out because I know exactly how it feels to be hungry and terrified of eating at the same time.