It is thought that around 12 million Americans suffer from food allergies. Many of these people rely on a ‘self diagnosis,’ believing that they are allergic to certain ingredients and therefore should avoid eating such foods. Unfortunately, self diagnosis can lead to misdiagnosis. Many of those with food allergies are restricting their diet unnecessarily, because they actually suffer from asthma, not an allergy.
A true food allergy is a reaction involving the immune system. The immune system attacks a protein in the food that it identifies as foreign or harmful. It produces antibodies that lead to symptoms such as facial swelling, skin rashes, wheezing, and difficulty breathing.
Many of these symptoms of a food allergy are similar to those experienced during an asthma attack, which can lead to confusion between the two. True food allergies are nearly always caused by one of a few major food allergies, such as allergies to fish, shellfish, egg, milk, wheat, soy, peanuts, and tree nuts. Many other people experience asthma or hives after eating food containing certain food additives or preservatives. These asthmatic reactions do not involve the immune system, and therefore are not true food allergies.
It is believed that food-triggered asthma accounts for five to ten percent of those with asthma. The most common foods to trigger asthmatic symptoms include sulfites (found in dried fruit, wine, bottled lemon, and lime juices, shrimp, and prepared potatoes) as well as the common food allergens listed above. There are also a number of ingredients tentatively linked to asthma, although more research is needed to conclusively label them asthma triggers. These include artificial dyes and colors, preservatives, aspartame, nitrite, and monosodium glutamate (or MSG).
As with true food allergies, the best way to avoid asthma triggered by food is to avoid eating the food that triggers symptoms. Because of the possibility of misdiagnosis, it is important to see a doctor for a proper diagnosis if you think that you have asthma or a food allergy.