Egg: A Top 9 Food Allergen

Egg

Egg allergy (hen/chicken egg), along with milk, is one of the most common allergies in children.

There are as many as 23 proteins in egg, but most of the allergens are in the egg white, not the egg yolk. There are three major proteins of concern in egg white: ovalbumin, the major allergen present in the highest proportion; ovomucoid, another egg white protein responsible for the majority of allergic reactions; and ovotransferrin. Egg yolk is an allergen but is not responsible for many reactions. Egg yolk cannot be safely separated from residual egg white protein allergens (e.g. strained egg yolk is not safe for an egg allergic individual).

Egg allergy is unique in that 70 to 80 percent of egg-allergic patients may tolerate egg that has undergone extensive baking (greater than 350 degrees F for 30 minutes, called “baked egg”) and are thus able to consume baked egg in pastries, breads, and cakes. Ovalbumin in particular is broken down and not able to bind IgE after such heating. However, ovomucoid is heat-stable, and patients who are allergic to ovomucoid tend to not tolerate baked egg. One study noted that patients who were baked-egg tolerant and regularly consumed baked egg were able to tolerate all forms of egg faster than those who could not tolerate baked egg. Wheat in baked goods may prevent the egg from being absorbed and recognized by the body.

Egg allergy is generally outgrown in childhood. One study showed that 66 percent of egg-allergic children tolerated egg by age 5, although nearly one-third of children with high egg-specific IgE levels and children with other food allergies may still need to avoid eggs at 16 years of age.

To confirm egg allergy, an Oral Food Challenge (OFC) can be performed in a clinical setting with a board-certified allergist. OFC’s are also used to confirm tolerance of baked egg. Consult with a board-certified allergist for further instructions on preparing egg in baked goods and the timing of either a baked egg or egg OFC – risks may be involved, and not all patients are proper candidates. In an Australian study of one-year-olds, 80 percent of children who failed a food challenge to egg were tolerant of baked egg. However, the best time to attempt a baked egg challenge is unclear.

Baked Egg Diet: What Is and Is Not OK?

It is essential to discuss with your allergist before introducing baked egg, since it is possible that eating foods containing baked egg may result in anaphylaxis. Check with your allergist or dietician for more specific guidelines, but in general, published data indicates the following guidelines[1]:

Allowed:

Egg listed as the third ingredient or lower on the ingredient list.
Home-baked items cooked at a minimum of 350 degrees F for at least 30 minutes that contain no more than two eggs per recipe batch.
Home-baked goods with a thoroughly cooked center (not moist/soft). Individual sized products (cupcake, brownie, muffin, etc.) are generally preferred to pieces of larger, full sized items because it is easier to make sure the center is fully cooked.

Not Allowed:

Caesar salad dressing
Custard
Egg listed as the first or second ingredient
French toast
Frosting
Home-baked goods in full-sized products (cookies, cakes, pans of brownies) where it is hard to tell if the center is cooked through
Home-baked products with more than two eggs per recipe batch
Ice cream
Mayonnaise
Meringue cookies
Pan-cooked egg of any style
Pancakes made from scratch or a mix
Quiche

Egg is an important source of dietary fat and protein. To replace these dietary benefits, egg-allergic individuals may need to look at other food sources. A consultation with a nutritionist who has experience with food allergies may also be helpful to ensure balanced and adequate nutrition.

Other Sources of Protein

Beans*
Fish*
Grains* (such as wheat germ)
Legumes*
Meat
Milk*
Soy*

Other Sources of Fat:

Avocado
Dairy products including butter, whole, or 2 percent milk*
Fatty fish*
Meat products
Nuts*
Polyunsaturated and monounsaturated fatty acids (vegetable oils such as olive, canola, safflower, sunflower, soy, corn, peanut, and cottonseed oil)
Seeds*

* These are among the most common allergenic foods. However, almost any food can cause an allergic reaction. Check with a board certified allergist before adding any new foods to your.

Avoid foods that contain egg ingredients, such as:

Albumin
Egg (white, yolk, dried, lecithin, powdered, solids)
Egg substitutes
Egg nog
Egg noodles
Globulin
Lysozyme (used in Europe)
Mayonnaise
Meringue
Ovalbumin
Ovovitellin
Surimi

Egg in Unexpected Places

Shiny coats/glazes on pastries/candies. These may be egg washes. Candy dots, lollipops, and soft pretzel glazes are possible examples of this.
Many egg substitutes may contain egg.
Many pastas sold in stores contains egg, both dried and fresh.
Foams on coffee drinks may contain egg.
Egg white and egg yolk cannot be separated without cross-contamination.
Lecithin (most soy lecithin does not contain egg, but double check).
Marshmallows, marzipan, and nougat may contain egg.

NOTE: Please keep in mind in a culturally diverse world, different ingredients may be used in different recipes. Always use extreme caution.

Egg-Containing Vaccines: FAACTs to Know

Influenza vaccine (injectable and nasal) and the Measles, Mumps, Rubella (MMR) vaccine have been repeatedly shown to be safe even in individuals with egg allergy. There is still a general precaution for Yellow Fever vaccine that remains unchanged.

Since 1995, the MMR vaccine has been considered safe for all egg-allergic recipients and should be routinely administered in the primary care setting.
Since 2011 the CDC and AAAAI/ACAAI both have recommended that egg allergic individuals receive influenza (prior to this it was often withheld or only given at an allergist’s office under a special procedure).
Furthermore, allergy testing to the vaccine and multiple dose vaccine desensitizations are no longer necessary.

Injectable influenza vaccine is safe to egg-allergic children of any severity (including egg anaphylaxis) as a single dose, without testing to the vaccine.

However, at this time, the CDC and American Academy of Pediatrics recommend that only egg-allergic children with a history of developing just hives after consuming egg should receive the influenza vaccine in the primary care setting (e.g with their pediatrician), and that patients with a more severe history of reactivity should receive the vaccine from a board-certified allergist.

However, to repeat, influenza vaccine is safe for any individual, including those with past severe reactions to egg, despite recommending that only the children with very mild past reactions to egg receive this in the primary care setting.

Practical Tips

Avoid egg and products containing egg.
Always carry at least two (2) epinephrine devices at all times if you have been diagnosed with an egg allergy. This is in case one misfires or if symptoms return and a second dose is needed.
Seek emergency medical assistance immediately after using an epinephrine auto-injector. This is due to the possibility of a biphasic reaction. A biphasic reaction is when a second reaction occurs due to the initial allergen exposure. Stay in medical care for at least 4-6 hours.
Read all product labels prior to eating a new food product. According to the Food Allergen Labeling and Consumer Protection Act (FALCPA), food products with advisory statements such as “may contain” or “manufactured in facility that processes” are voluntary. Manufacturers are not required to include these advisory statements. Whether or not the statement appears on a product has no bearing on the product’s safety. The absence of the statement also does not necessarily mean that product may have not been exposed to cross-contact. Cross-contact is when a food item has been manufactured on shared equipment with an allergen (for example, egg) during the manufacturing process. Contact the manufacturer to confirm the safety of a product.
Cross-contact can also occur when utensils or equipment are shared, such as cooking and serving utensils. For example, a spatula that was used to cook pancakes or a knife used to spread mayonnaise. These utensils are now contaminated and no longer safe for an egg-allergic individual.
Cooking utensils should be thoroughly washed with soap and water after each use.

Visiting restaurants can be a pleasant experience for family and friends to gather together. However, some restaurants may pose a food-allergy risk. There is also the risk of cross-contact even if an egg-free item is ordered. Please visit our 'Dining Out' page for tips on how to manage visiting a restaurant.

Other pages that may be of interest:

Visit FAACT's CROSS-CONTACT page to review how to properly clean allergens from hands and surfaces.

References

[1] Adapted from Groetch and Nowalk-Wegryzn, Pediatric Allergy and Immunology 2013 (24: 212–221).