There is a lot of confusion (and confusing information) about food allergies both in the general population and the medical communities. Hopefully the following can help you navigate through the “maze”.
Food Allergy: Means your body forms IgE antibodies to one or more of a food’s protein or carbohydrate structures or elicits a T-cell recognized allergen response. In the IgE or B-cell pathway, when you eat the offending food, IgE antibodies that have learned to recognize those specific components as enemies, trigger the mast cells they rest on to release substances that cause the symptoms. These mast cells line your skin, respiratory, and GI tract. The substances they release can cause symptoms ranging from minor mouth itching all the way to throat closure, hives, severe asthma attacks, or even shock. These reactions can be deadly for some people and tend to happen rapidly. Even small quantities of the food can cause symptoms. Although not as well understood, in the T-cell pathway, symptoms tend to take longer to manifest themselves but are usually more related to skin issues (eczema) or more delayed vomiting or diarrhea (protein induced enterocolitis and similar syndromes are thought to be t-cell driven). Since the T-cell pathway is more difficult to determine, the focus of this paper is primarily on IgE mediated food allergy. 1,10
Food Intolerance: Means you may lack certain enzymes to help digest the food. Generally small amounts of the offending food can be tolerated but larger amounts often cause symptoms. Lactose Intolerance is an example of a food intolerance. 1
Food Auto-immune Response: This means that a food when eaten can cause your body to produce different types of antibodies that attack your own tissues. This does not occur if the food is not eaten. Celiac Disease is an example of this this type of food
An accurate history is the most important factor in helping to track down a possible food allergy. What was eaten? What type of symptoms took place? How long did it take the symptoms to start after eating the suspect food? What actions were taken and what was their effect? Most often true food allergy will cause symptoms to occur within the first 2 hours and will usually involve one or more of the following:
itching (mouth or generalized), swelling of lips, tongue, or throat; hives; cough, wheeze, or shortness of breath; abdominal or esophageal pain; vomiting or diarrhea; loss of consciousness; shock or even death. 6
Likely Suspects: The following eight food types are the culprits in over 90% of food allergies. 1
The following steps can help determine if you have a food allergy:
For yet un-established reasons, food allergy and its severity is on the rise. More people are becoming affected and are having severe reactions. This has accelerated within the last few years and is especially true with children. Its also more common now to see adults whom have eaten a food all of their lives suddenly manifest allergic symptoms from ingestion. Research is underway to try and figure out why this is happening.5
Several studies demonstrate that people can be desensitized to foods that have previously caused allergic reactions. This is a very exciting and promising area that is developing rapidly. 8
1. Board, A.D.A.M. Editorial. "Causes, Incidence, and Risk Factors." Food Allergy. U.S. National Library of Medicine, n.d. Web. 08 July 2012.
2. Caubet, Jean, R. Bencharitiwong, E. Moshier, J. Godbold, Hugh Sampson, and A. Nowak- Wegrzyn. "Significance of ovomucoid- and ovalbumin-specific IgE/IgG(4) ratios in egg allergy." National Center for Biotechnology Information. U.S. National Library of Medicine, n.d. Web. 08 July 2012.
3. Celiac Disease Foundation. N.p., n.d. Web. 08 July 2012.
4. Eckman, John, Sarbjit S. Saini, and Robert G. Hamilton. "Diagnostic Evaluation of Food-
related Allergic Diseases." Allergy, Asthma & Clinical Immunology 5.1 (2009): 2. Print. 5. "Food Allergy Facts and Statistics for the U.S." - FAAN. N.p., n.d. Web. 08 July 2012.
6. "Guidelines for the Diagnosis and Management of Food Allergy in the United States." Clinical Practice Guidelines. N.p., n.d. Web. 08 July 2012.
7. Noh, Geunwoong, Hyun-Sook Ahn, Nam-Yun Cho, Sangsun Lee, and Jae-Won Oh. "The
Clinical Significance of Food Specific IgE/IgG4 in Food Specific Atopic Dermatitis." Pediatric Allergy and Immunology 18.1 (2007): 63-70. Print.
8. Nowak-Wegryzn, Anna, and Hugh A. Sampson. "Future Therapies for Food Allergies. "Journal of Allergy and Clinical Immunology 127.3 (2011): 574-75. Web.
9. Okamoto, S., S. Taniuchi, Y. Hatano, K. Nakano, T. Shimo, and K. Kaneko. "Predictive Value of IgE/IgG4 Antibody Ratio in Children With Egg Allergy." Allergy, Asthma & Clinical Immunology 8.9 (2012): n. pag. Web. 8 July 2012.
10. Philippe A Eigenmann, Christophe P Frossard “The T Lymphocyte in Food-Allergy Disorders”Curr Opin Allergy Clin Immunol. 2003;3(3)