The starting point is your detailed food and symptom diary (p.187). The longer and more accurately this is completed, the more likely it is that patterns can be identified. Analyse your diary for the *balance and variety* of food groups and food types, not just for potentially problematic foods. If you need support with the analysis ask your family doctor for a referral to a registered dietician.
Your digestive health is affected by many factors: diet/ nutrition, physical activity, stress, sleep patterns, weight, genetics, hormones, medication and more. Make changes to your diet or lifestyle slowly one at a time (p.190 + 193). Positive, neutral or negative effects can depend on the quantity of a food or food type, and how often it is eaten.
It is possible to minimise kitchen time whilst still eating healthily, especially if you have a freezer, slow cooker/ crock pot, stick blender, microwave oven.
Frozen vegetables and fruits, canned beans lentils and tomatoes, canned oily fish, cooked smoked fish, frozen seafood all need minimal preparation. It is possible to throw the ingredients for a stew/ casserole/ soup into the slow cooker in literally five minutes. Go about your day and come home to a hot meal.
HTH!