You may receive a diet questionnaire, be asked to prepare a food intake history, receive skin tests, or blood tests, or be asked to have a food challenge in a controlled clinical setting. Moderator Let's go into sensitivities. In the truest definition of food sensitivity, the most common example is lactose intolerance. Lactose intolerance occurs because of a deficiency in an enzyme to break down lactose, the sugar or major carbohydrate component of milk and dairy products. Generally, the symptoms of lactose intolerance can mimic some of the symptoms of food allergies that are generally annoying rather than life threatening.
People often experience bloating, gas, or diarrhea when they have lactose intolerance.
If someone is to have a true food allergy, the first ingestion of that food, or sensitization, may not result in any reaction at all. At that point, one's immune system will create the immunologic response to treat the allergen as an invader for future occurrences. Generally, it is the second occurrence and future occurrences of a food allergen that create allergic responses. Yes, it's generally unusual to be lactose intolerant. Most people can tolerate milk, and even those who are lactose intolerant can tolerate moderate amounts of lactose when combined with a meal.