Fresh bread is difficult for the stomach to digest, and this can lead to a flare-up of gastritis in people who already have it. In addition, freshly baked bread begins to ferment in the intestines, leading to the formation of excess gas, which causes cramps and intestinal pain. In the past, fresh bread did not have such a negative effect on the body. This is because bakers in the past used natural sourdough starters in their bread dough, whereas today synthetic yeast is added.