Food allergies occur when the body has an abnormal reaction to a food eaten or touched. Symptoms of food allergy vary and can include:
- tingling of the mouth, arms or legs;
- rash, hives or itching;
- abdominal cramps, vomiting or diarrhea;
- breathing difficulties;
- swelling of the tongue or the throat;
- loss of consciousness.
Allergic reactions to food may be serious and should be discussed with a doctor. A food that did not previously cause any reaction may suddenly cause severe allergic symptoms. When this occurs, the body produces a substance called histamine what causes blood vessels to dilate. The most serious symptom of food allergy is anaphylaxis (anaphylactic shock), a sudden and potentially life-threatening body reaction to an allergen.
The treatment for anaphylaxis is medication called antihistamine. If taken immediately, this antihistamine can stop anaphylaxis before it becomes too serious. In cases of severe allergy, an injection of a strong antihistamine called epinephrine or adrenaline may be needed.
Children of parents who have a significant allergic reaction to a food are more likely to have that food allergy as well. To identify food allergies, a doctor or a dietitian records a medical history. The patient keeps a food diary documenting exactly what and when is eaten and also records physical symptoms and when they occur. Other means of diagnosis food allergies can include skin test and food challenge test.
Food allergies may be prevented by avoiding foods that cause allergic reactions (elimination diet). Foods that cause up to 90% of all food allergies include milk, eggs, peanuts, tree nuts (walnuts, cashews, pecans, etc.), fish, shellfish, soy, wheat. Once a food allergy has been identified, an elimination diet is the only effective treatment.
If food allergy is suspected, it is necessary to consult a doctor or a dietitian. Removing foods from the diet can cause an unbalanced diet that may be deficient in necessary nutrients. Since some of the most common foods that cause allergies include milk, eggs, and wheat, significant sources of protein, calcium and fiber may be removed. In this case, the diets should be modified and safe substitutions be found to ensure that all necessary vitamins and minerals are maintained in the diet. It is especially important to maintain a balanced diet in children during years of development.
Registered Dietitians in the Nutrition & Health Center also provide other medical nutritional care at different medical conditions like: