Perhaps it is not directly related to what the subject is trying to tell, but if you are suffering from gastric ulcer disease, the amount of acid going to stomach decreases as you do not eat, so the pain is reduced accordingly. When food is reduced in the same way, if you exhibit a high activity of movement, the load on the heart is reduced and the tension-related headaches and stenocardia-related pain are diminishing. Likewise, if you eat heavy meals last day, you know well the pain your intestines have caused to you the next day. All of this can be explained as food-dependent pain, which can be explained differently from inflammatory pain.