Food Allergies – What Are They and Do You Have Them?

Fresh Littleneck ClamsFood allergies are a common problem for many people. It is common for people to label a reaction to a food as a food allergy, when many times the correct diagnosis is a food sensitivity. What is the difference? Let our Black & Kletz Allergy specialists provide the answers.

Food Allergy:

A food allergy is when an individual has an immunologic relation to a particular food. The most common and most potentially dangerous immunologic reaction is called an “IgE-mediated” immunologic reaction. This occurs when an individual’s Immunoglobulin E (IgE) antibodies react against a specific food. If the reaction is severe enough, it can be life-threatening. How does this happen? Your body is exposed to foods before you are born! The food that your mother eats comes in contact with the fetus via the placenta which makes it possible for very young babies to develop these IgE antibodies which will cause them to have food allergies. Adults, on the other hand, will develop these IgE antibodies just by constant exposure to a food. Food allergies usually develop early in life but can occur at any age. The most common food allergies in infants and children are egg, milk, soy, wheat, peanuts, and tree nuts. The most common food allergies in adults are shellfish, fish, peanuts, and tree nuts. Infants and children can “outgrow” their food allergies, however, peanut and tree nut allergies tend to stay. Adults, on the other hand, tend not to “outgrow” their food allergies.

A Word About Peanut Allergies and Other Serious Food Allergies:

Many people are confused about peanuts. Peanuts are actually not nuts. They are “legumes.” It is therefore possible to be allergic to peanuts, but not nuts that grow on trees, commonly referred to as “tree nuts.” The incidence of peanuts, particularly in children is increasing and as of today, about 1.2% of children have a peanut allergy. If someone has a peanut allergy they are more likely to have or develop an allergy to beans, lentils, peas, soybeans, etc. It is imperative for anyone with a peanut allergy to always read the ingredients, let family and friends know about their allergy, and carry a self-dosed Epinephrine device such as an EpiPen, EpiPen Jr., Auvi-Q 0.3, Auvi-Q 0.15, etc. with them at all times. Some people are so allergic to peanuts that simply being in the proximity to peanuts will cause a severe reaction. The other foods that tend to cause the most fatalities besides peanuts are tree nuts, shellfish, and fish. It is also very important for these individuals to also always read the ingredients, let family and friends know about their allergy, and carry a self-dosed Epinephrine device such as an EpiPen, EpiPen Jr., Auvi-Q 0.3, Auvi-Q 0.15, etc. with them at all times. Note that any food can cause a severe anaphylactic life-threatening reaction, however, peanuts, tree nuts, shellfish, and fish are the most common food allergies that cause such reactions.

Oral Allergy Syndrome (Pollen-Food Allergy Syndrome):

Oral Allergy Syndrome (OAS) is a type of food allergy where the individual must have a pollen allergy even if they are not aware of it. It occurs when one eats uncooked or raw fruits, vegetables, and occasionally some nuts and other foods. The symptoms are primarily itching of the mouth, throat, and/or lips. Occasionally, people will experience itching of their hands when touching the raw foods. The syndrome is caused by allergens in foods that derive from plants. Therefore, only foods that come from plants can cause OAS. Extra caution needs to be taken in cases where nuts cause symptoms because many individuals can have nut allergies that are not associated with plants and as discussed above, may be life-threatening. Ironically, when the food is cooked or canned, the protein is denatured and destroyed which usually prevents the allergic reaction from occurring. In most cases, people with OAS can tolerate cooked and/or canned fruits and vegetables. Common examples of foods associated with OAS include birch tree pollen allergy and its association with the following foods: apples, pears, peaches, plums, apricots, cherries, and/or carrots. Ragweed pollen allergic individuals may have the symptoms from melons, bananas, and/ or kiwi.

Food Sensitivity:

A food sensitivity is not an immunologic reaction, but still is real and can cause a variety of problems. Below are 3 such food-related non-allergic conditions. Note that there are many more types of food sensitivities and food intolerances that are not mentioned below.

Lactose intolerance is often misdiagnosed as a milk allergy. When an individual has lactose intolerance they are lacking the enzyme called “lactase” that breaks down the sugar “lactose” that is present in milk and other dairy products. People with this condition should be tested for milk allergy to rule that out and if negative, they generally do well either by avoiding lactose or by drinking alternative milks such as Lactaid (lactose-free milk) soy, rice, and/or almond milk. They can also generally tolerate dairy products by using Lactaid pills which re-introduces the enzyme lactase to their system that they lack.

Gluten intolerance is becoming more of an issue over the last decade. Gluten is a protein found in many common grains. Gluten intolerance is different than a true gluten allergy as allergy testing to the different glutens (wheat, barley, rye, etc.) is negative with gluten intolerance. Whether someone is allergic or not allergic, the treatment is the same, which is to avoid gluten. Always make sure that any food you eat says “Gluten-free” on its label. Persons with celiac disease must make sure that they eat no gluten as there are consequences other than abdominal discomfort and these individuals should also be checked and followed by a Gastroenterologist.  Recent research suggests that it may be the inability to digest a group of carbohydrates called FODMAP’s (fermentable oligo-, di-, mono-saccharides and polyols) that may be the cause of gluten intolerance rather than the gluten itself, as wheat, barley, and rye are high in FODMAP’s.

Food dyes and preservatives can cause allergic-like symptoms and should be thought of when assessing a person who exhibits symptoms of food allergies. Since there are no reliable tests for these, a detailed history needs to be taken and other foods may need to be ruled out in order to diagnose food dyes and preservatives as the problem.

We Can Help You:

Since food allergies and food sensitivities/intolerances play an important role in many patient’s lives, the allergy doctors at Black & Kletz Allergy will take a detailed history, perform any necessary food testing and/or food challenges, provide education, and prescribe any medications that you may need to use in the event that you are exposed to the food or foods that cause your symptoms. Let our Washington, DC allergists suppress your allergy symptoms today.