All About Allergies

What are food allergens?
Food allergens are proteins that are not broken down by the heat of cooking or by stomach acids or digestive enzymes. They survive to enter the bloodstream, and go to the target organs, causing allergic reactions.

What are the most common food triggers?
Adults react most commonly to shellfish, nuts (especially peanuts and walnuts), soya, fish, eggs, dairy products, red wine, avocados and bananas. Children react to many of the same things and, additionally, to wheat.

What are the symptoms of allergies?
Reactions to consumed foodstuff may be either immediate or delayed. Immediate reactions — usually to foods like nuts, fish and mutton — include swelling of the mouth and tongue tissues and the eyelids, watering in the eyes and facial flushing. Delayed reactions (to wheat, soya and milk) could be gastric disorders, abdominal pain, skin rashes and asthma. Anaphylaxis is a life-threatening condition that occurs when several parts of the body react simultaneously to a food, causing difficulty in breathing, hives and swelling of the throat.

Once allergic, always allergic?
Usually, in the case of adults. Children, though, occasionally outgrow their allergies. Wheat allergy in children, however, is not easily shaken off.

How are allergies diagnosed?
‘‘Assessments have to be made with the help of detailed patient histories and studies of daily diets and elimination diets. Wheat allergy, though, can be determined only through three consecutive biopsies,’’ says Dr Anupam Sibal, senior consultant, Gastroenterology, at Indraprastha Apollo, New Delhi. Doctors and patients need to consider the timing of the reaction, if it is always associated with a certain food, if other people who had the same food developed the same reaction, if it can be associated with the amount of food, if the food was undercooked and if other food was consumed simultaneously.