Food Allergy
Food Allergies
Allergy can be triggered by many substances including food. It may appear astonishing but is a truth that millions of people (about 4 millions) in the United States suffer from food allergy. Think what would be like if drinking a glass of milk or eating a peanut butter sandwich left you vomiting and produce other undesirable consequences. This may not be case for all people but it can happen with the people suffering from food allergies.
Food allergy is nothing but hypersensitivity of the body immune system to certain foods. In other words food allergy is triggered due to an abnormal response of the body immune system to food. Unpleasant reactions like bloating and gas are not allergic reactions but are known to be caused due to food intolerance.
The fact that food allergies are difficult to identify makes it more difficult for a person to avoid foods that may cause allergic reactions. Anaphylaxis is the most dreaded form of food allergy. Other allergies caused by food are comparatively less serious. In Anaphylaxis person suffering from it experiences low blood pressure, constrict of airways in the lings, swollen throat or tongue resulting in suffocation.
It may appear astonishing but it a truth that about 150 people in United States succumbs to food allergies every year.
Considering the seriousness and widespread of the food allergy the FDA’s Centre for Food Safety and Applied Nutrition has given highest priority for rising awareness of food allergens amongst consumers and food manufacturers. Food and Drug Administration is conducting education programs on this aspect as a part of their drive for awareness of food allergens. To facilitate the easy-to-understand labeling of food allergens the FDA is formulating a strategy.
Allergic Reactions
Usually, food does not provoke any response from the immune system. Immune system is considered as body’s defense against health threats. According to the researchers at the National Institute of Allergy and Infectious Diseases, two parts of the body immune response are involved in food allergies. First is the immunoglobulin E (antibodies produced) and the other is a type of cell known as mast cell. Mast cells are present in all body tissues in general and in areas that are typical site of allergic reactions in particular. These typical sites include throat, nose, skin, gastrointestinal tract and lungs.
Normally the ability to form Ig E against food is inherited by the people. People with family history of allergies like hay fever, eczema or asthma are more prone to develop food allergies.
A predisposed person has to be exposed to a specific food before IgE is formed. When such food is digested first time, certain cells are prompted by the protein fragments to produce specific IgE against that specific food. This IgE then attaches to the mast cell surface. When that specific food is taken again, the interaction between protein and specific IgE (attached to mast cell surface) takes place resulting in release of chemicals like histamine. This triggering of histamine produces symptoms of allergic reaction. Itching of tongue, moth, swelling or difficulty in breathing experienced by the individual is due to release of such chemicals by mast cells in nose and throat. If the mast cells release chemicals in gastrointestinal tract the individual may have abdominal pain or diarrhea. Mast cells in skin can produce intense itching or hives.
Protein fragments in the food, those are responsible for allergic reaction, can not be broken down by stomach acids, cooking or enzymes. Proteins present in the food can travel through the blood flow, cross gastrointestinal lining and result in allergic reaction in the complete body.
The location and timing of food allergic reaction is affected by digestion. To elaborate, an individual may first experience severe itching of the tongue followed by vomiting, diarrhea or cramps. Afterwards, when the allergens travel to the different body parts through bloodstream he may experience low blood pressure, eczema or hives, and if the allergens reach lungs, asthma. This process may take varying times ranging from few minutes to couple of hours after the food has been taken.
Most likely suspects of Food Allergies
Food allergy patterns in adults are different from that of food allergy patterns in children. Shrimps, crab, lobster, shellfish, peanuts, walnuts and other nuts; eggs etc are examples of most common foods that can cause food allergies in adults. Normally adults do not outgrow or lose their food allergies.
Milk, eggs, soy and wheat are the main culprits responsible for occurrence of food allergies in children. Out of these children outgrow their allergies to egg, milk and soy and wheat. However, children can not outgrow their food allergies to tree nuts, peanuts, shrimp and fish. Food labeling is an important component in drive against food allergies. This helps people in avoiding food that contains ingredients to which an individual is allergic.
