Genetically Modified Foods hurt digestive health. GMO foods have been around for decades. They are detrimental because BIG AG has injected each crop with a bacterium that kills bugs and plays havoc on our GI system. Foods to avoid are corn, canola, sugar beets, alfalfa fed to animals, soy, potato, tomato, apple, pineapple, zucchini, and citrus. Buy these foods in organic form.