Egg allergy

What it is

An egg allergy happens when the immune system overreacts to proteins in egg whites, egg yolks or both.¹ The whites contain the proteins that most often cause reactions.³ Even so, the white cannot be completely separated from the yolk.¹

Hen’s egg allergy is among the most common food allergies in infants and young children, and is less common in older children and adults.³ Experts estimate that as many as 2 percent of children are allergic to eggs.¹ Most grow out of it: studies show that about 70 percent of children with an egg allergy outgrow it by age 16.¹ Some people stay allergic to egg throughout their lives.³

Chicken eggs are not the only concern. People allergic to them may also be allergic to eggs from other birds, such as goose, duck, turkey or quail.¹

Symptoms it causes

Symptoms can appear within a short time after eating eggs, or even touching them.¹ ACAAI lists vomiting, stomach cramps, wheezing, hives, swelling of the tongue or lips, dizziness and confusion among the possible signs.¹ FDA notes that a mild reaction does not always mean the allergy is mild.⁵

Reactions can range from mild, such as hives, to severe, and even very small amounts of egg can cause one.³ The most serious is anaphylaxis, a life-threatening reaction that affects the whole body and can impair breathing.² An allergist can test for an egg allergy.¹

Reading food labels

Egg is a major food allergen under US law. The Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA) named eight major food allergens, eggs among them, and the FASTER Act made sesame the ninth, effective January 1, 2023.⁴

A packaged food that contains egg must name it in one of two ways: in parentheses after an ingredient, or in a “Contains” statement next to or right after the ingredient list.⁴ Not every product that contains an allergen has a “Contains” statement, so FDA points readers to the whole ingredient list.⁶

FDA counts eggs from domesticated chickens, ducks, geese, quail and other fowl as eggs.⁷ For eggs from a bird other than a chicken, FDA says the label should also name the bird, as in “Contains eggs, duck eggs.”⁸

Phrases such as “may contain egg” or “produced in a facility that also uses egg” are advisory statements. FDA says they are not required by law. Manufacturers can use them for cross-contact that cannot be avoided, but only if they follow good manufacturing processes and have taken every precaution to avoid it, and the statements must be truthful and not misleading.⁴ FDA calls the “may contain” statement voluntary, and not all manufacturers use it.⁶

Egg can be a hidden ingredient. ACAAI names canned soups, salad dressings, ice cream, and meat dishes such as meatballs and meatloaf, and warns that even some commercial egg substitutes contain egg protein.¹ FARE’s list of ingredient names that point to egg includes albumin (or albumen), lysozyme, meringue, ovalbumin, ovomucoid and surimi.³