Avoid fried foods, greasy foods such as potato chips and spicy bagels or breads. Fruits and Vegetables If you have ulcers, eat fruits that are low in acid, such as apples, peaches, pears, grapes, kiwifruit, bananas, berries and melons. Avoid all citrus, as high-acid oranges, grapefruit, tangerines, lemons and limes may increase stomach acids. Consume vegetables that do not cause you pain, discomfort or excess gas.