If you have gum pain when eating sour food, it is likely that your gums have been traumatized and will become painful once you eat irritating food. At this time, patients are advised not to eat foods that are too acidic, too spicy or too irritating, and to wait until the gum wounds have healed so that they can chew food normally. Gum wounds may be burns or contusions, and if the patient eats too hard food or the oral environment is dry, it may cause damage to the gum mucosa, which will heal on its own within a week or so and does not require any treatment. However, if the gum pain lasts for a longer period of time, it is still important to visit the dentist as soon as possible to see if there are other mucosal diseases in the mouth, such as lichen planus or white spots, both of which may cause sensory abnormalities due to eating irritating foods.