Living with Food Allergies

Judy Seybold, MS, RDN, LD, CLC
Chief Nutrition Officer

The causes of a food allergy are not well understood, and the symptoms can range in severity. A food allergy occurs when your immune system mistakes a food as harmful. Your body reacts to fight the food, by releasing immunoglobulin E (IgE) that will neutralize it. A food allergy can develop at any time in your life; food you previously enjoyed can suddenly become unsafe for you.

Food allergens are unpredictable. A previously mild reaction does not ensure all future reactions will be mild. The most severe reactions can progress very quickly into anaphylaxis, where blood pressure drops, the airways narrow, and the person loses consciousness. Without immediate treatment with epinephrine, an allergic person may die from an anaphylactic reaction. Other symptoms of a food allergy may include: itching in the mouth, hives, swelling in areas on the face, nasal congestion, difficulty breathing, abdominal pain, diarrhea, nausea, vomiting, dizziness, or fainting.

Food allergies and food intolerances are not the same, and many symptoms of a food allergy may be the same or similar to those of other medical conditions. If you suspect that you or your child has a food allergy, seek evaluation by an allergist. A food allergy is typically diagnosed through a combination of reaction history, skin prick testing, and serum IgE blood test. Oral food challenges, which are controlled exposures under the care of an allergist, are sometimes done to test if a patient has outgrown an allergy.

Generally, food allergy reactions begin within a few minutes of eating the food, but can take up to two hours. Mild food allergy reactions are generally treated with an antihistamine. Severe reactions involving anaphylaxis are treated with epinephrine. Most people with life-threatening allergies carry auto-injectors for epinephrine, sold under the brand names Epi-Pen®, Auvi-Q®, and Adrenaclick®. Early use of epinephrine is the best treatment for anaphylaxis.

Top 8 Food Allergens in the U.S.

• Egg: An egg allergy requires avoiding egg cooked by itself or used as an ingredient, such as in cakes. Egg protein is also present in some vaccines.
• Fish: An allergy to finned fish, such as halibut, salmon or tuna, most typically develops in adults. Fish products are also found in some salad dressings and fortified orange juice. Fish and shellfish allergies are not related – people can be allergic to fish or shellfish or both.
• Milk: A cow’s milk allergy is the most common food allergy in babies and young children. Avoiding cow’s milk includes avoiding these products commonly made with milk: cheese, butter, margarine, yogurt, cream, and ice cream. Note that “non-dairy” on a label does not necessarily mean a food is safe, as it may contain caseinates.
• Peanut: Peanuts are not true nuts – they are legumes – so having a peanut allergy does not mean someone is automatically allergic to other types of nuts. Avoiding peanuts requires avoiding peanuts and all peanut-containing products.
• Shellfish: An allergy to shellfish includes crab, crayfish, lobster, scallops, shrimp, and mussels. Most people allergic to one type of shellfish are also allergic to other types, so most avoid all shellfish.
• Soy: A soy allergy requires avoidance of soybeans or soybean-containing products. Soy is prevalent in many processed foods, including baked goods.
• Tree Nuts: Tree nut allergens include almond, Brazil nut, cashew, hazelnut, pecan, pistachio, and walnut. People can be allergic to one or more tree nuts. Tree nut oils are also widely used in personal care products, including soaps and lotions, and can cause reactions.
• Wheat: An allergy to wheat requires people to completely avoid wheat-containing foods. Wheat is also found in many beauty products.

Sesame allergy is also quite prevalent in the U.S., though labeling for this allergen is not mandatory. And while the allergens mentioned above are the most common, someone can be allergic to just about any food. Gain transparency about the foods you eat from trusted sources of information and always read food labels and ingredient statements.

Shopping for a Food Allergy

When preparing food for a food-allergic person, be sure to ask questions so that you clearly understand what allergen(s) they are allergic to. For packaged food items, it is important to read ingredient lists for an allergen every time a food is purchased because ingredient labels – and ingredients – often change without warning.

Most packaged foods in the U.S. are labeled clearly with a common term if they contain one of the Top 8 allergens. A common term makes it easy to find the allergen when the actual form may be less clear. For example, for a milk allergy, “whey” is a form of milk, but on most U.S. food labels, it will also be labeled as milk in the ingredient list as in “whey (milk),” or there will be a statement after or near the ingredient list stating, “Contains Milk.”

Even though people with food allergies often avoid cross-contaminated foods, which include those produced in facilities with other allergens or as processing aids, there is nothing mandatory stating a company must include information that a product “may contain” allergens unless they are specifically in the product. Ask questions of manufacturers when purchasing food for someone with a food allergy. Locally-made foods, such as those sold in a small bakery or farmers market, do not always have complete ingredient information on labels. Items imported from outside the U.S. should be examined closely.

Food Intolerances

While food allergies involve your immune system, food intolerances involve problems digesting a particular food. Symptoms of food intolerances tend to be limited to the digestive system, including an upset stomach, diarrhea, constipation, or gas. Intolerances are not life-threatening. Common intolerances are lactose, the natural sugar in milk, or gluten.

Learning how to safely shop for and prepare foods at home, and eat away from home, are challenging with a new food allergy diagnosis. A registered dietitian can help provide important guidance as you learn how to live with your allergy.

Shop Sifter for products that are free from common allergens:

Casein - None
Corn - None
Dairy - None
Eggs - None
Gluten - None
Lactose - None
Mammalian Meat - None
Milk - None
Mustard - None
Nuts - None
Peanuts - None
Sesame - None
Shellfish - None
Soy - None
Sulfites - None
Tree Nuts - None
Wheat - None

Additional Resources

Food Allergy Research & Education (FARE)
American College of Allergy, Asthma & Immunology
Academy of Nutrition and Dietetics: Allergies and Intolerances