Food allergy is an abnormal response to food that is triggered by a specific reaction in the system. It is expressed by certain, often characteristic, symptoms. These adverse reactions are prompt and place; common sites are the mouth (lip swelling), digestive tract, the airways (breathing problems) and the skin.
FOOD ALLERGY: WHAT, WHY, WHO AND WHEN
Food allergy is an abnormal response to food that is triggered by a specific reaction in the system. It is expressed by certain, often characteristic, symptoms. These adverse reactions are prompt and place; common sites are the mouth (lip swelling), digestive tract, the airways (breathing problems) and the skin. This difference between the prevalence of clinically proven food allergy and the public's perception of the problem is due primarily to misinterpretation of food intolerance or other adverse food reactions to food as food allergy. A food allergy causes a specific immunological reaction in the body that can be observed and diagnosed by different tests.
Food hypersensitivity refers to all types of overreactions that an organism can have against a food component. Hypersensitivity on food can be divided into food allergies and food intolerance. Both refer to abnormal reactions to otherwise safe foods.
What is food intolerance?
Food intolerance is an adverse reaction to a food triggered by a food or food component, e.g. lactose intolerance. It does not involve the immune system. The reaction is due to non-digestion/absorption of a specific food or food component.
For example, people with lactose intolerance do not have the enzyme lactase to digest the sugar, lactose, in milk. This is one of the most common food intolerance occurring in nearly 50% of the adult world population, mostly in Asia. Some people have intolerance against additives such as flavor enhancers (MSG) or preservatives (sulphite). The symptoms varies among individuals and often impossible to determine which food component causes which reaction.
The symptoms of food intolerance can be mistaken for those of a food allergy. It is important to consult a physician to determine the causes of a reaction to food.
The causes of food intolerance are complicated. The reason differs from different components; possible mechanisms are the lack of a particular enzyme (enzymes are needed for specific chemical reactions in the body), heredity, stress or illness, an impaired immune system, environmental disturbances and lack of proper nutrition.
Why are some people allergic to some ingredients?
Genetic history is one of the best predictors of the likelihood of having a food allergy or intolerance. Children of allergic parents are more likely to have an allergy. Infants with one atopic parent have about twice the risk of developing food allergy as infants whose parents do not have allergies. If both parents are atopic, the risk increases from four to six times. For babies that are born into families where close relatives suffer from allergies, exclusive breast-feeding for 4-6 months seems to give some protection.
Who suffers and when do allergies occur?
A food intolerance or allergy can occur at any age, some short-term or a lifelong condition. If not identified early, food intolerance symptoms can lead to more serious problems in later life: for example, colitis in a child that is caused by lactose intolerance can lead to Crohn's disease in adulthood.
Food allergy may appear at any age but true allergic reactions to foods are most common in infants and young children and decreases with age. It is estimated that about 2% of all adults have a food allergy.
Children of parents who have a history of food allergies have an increased susceptibility to allergies. Children with food allergies should be re-evaluated regularly; often, they outgrow their problems and no longer need restricted diets.