Posted on February 9, 2010.
The ABCs of Food Allergies Approximately 8% of children and 2% of adults suffer from true food allergies. When the culprit food is eaten, most allergic reactions occur within minutes. The skin symptoms (itching, urticaria, angioedema) were the most common and occur in the reactions of most foods. Other symptoms may include nasal (sneezing, runny nose, itchy nose and eyes), gastrointestinal (nausea, vomiting, cramps, diarrhea), lung (shortness of breath, wheezing, coughing, chest tightness), vascular and blood pressure (low, light headache, rapid heart beat) symptoms. In severe cases, this reaction is called anaphylaxis and can be fatal.
Allergy or intolerance?
Most reactions to food are probably not allergic in nature, but rather of intolerance.
This means that there is currently no antibodies against food allergies in people. Intolerance can be classified as toxic and nontoxic. Toxic reactions would be expected to occur in most people if a sufficient number of food was consumed include alcohol, caffeine or food poisoning. nontoxic food intolerance occurs in some people, such as lactose intolerance, which is due to the lack of lactase, the enzyme that digests the milk sugar and dairy products. Patients with bloating, lactose intolerance experience cramps and diarrhea within minutes or hours after eating food containing lactose, but know no other symptoms of food allergies.
Non-allergic immune reactions
A less common form of non-allergic reactions to food implies the immune system, but there is no allergic antibodies present. This group includes celiac disease and spies (food protein-induced enteropathy syndromes). Spies usually occurs in infants and young children, gastrointestinal symptoms (vomiting, diarrhea, bloody stools, and loss of weight) that the signs presented. Milk, soy and cereals are the most common triggers in the spies. Typically, children grow spies 2 to 3 years.
Common Childhood Food Allergies
Milk, soy, wheat, eggs, peanuts, tree nuts, fish and shellfish compromise more than 90 percent of food allergies in children. Allergy to milk and eggs are by far the most common, and are generally beyond the age of 5 years. Peanuts, nuts, fish and shellfish allergies are usually the most serious and potentially fatal, and often persist into adulthood.
Cross-reactivity and cross-contamination
Cross-reactivity refers to a person with allergies to foods like within a food group. For example, all shellfish are closely related, if a person is allergic to shellfish, it is likely that this person is allergic to other shellfish. The same applies to tree nuts like almonds, cashews and walnuts.
Cross-contamination refers to a food contaminating another, unrelated food led to a "hidden allergies". For example, peanuts and walnuts are not related to food. Peanuts are legumes, and related to family of beans, while the nuts are true nuts. There is no cross-reactivity between the two, but both can be found in the candy store and a box of mixed nuts, for example.
The diagnosis of food allergies
Diagnosis is made with a history of an appropriate response to a specific food, with a positive test for antibodies against that food allergy. Testing for antibodies is usually performed with allergic skin tests, but can be done with a blood test as well.
The blood test called RAST is not as good as a testing of the skin but can be useful in predicting whether a person has passed a food allergy. This is particularly true given that in many cases, the skin test may still be positive in children who have actually exceeded food allergies.
If the diagnosis of food al.
