In the time it takes to make your bed in the morning or brush your teeth at night, a person has been admitted to the emergency room due to a food allergy. Food allergies are a major health concern worldwide responsible for sending someone to emergency medical care every three minutes.

The cause of food allergies is unknown, but their mechanism is the same: A person’s body mistakes certain nutrients in a food as harmful, which triggers an inflammatory response that can threaten the person’s health—and even cause their death. Food allergies and adverse reactions can arise at any age and may come and go throughout a person’s life. The outcome of a reaction can range in severity from mild (causing rashes, hives, and other external signs of inflammation) to severe (for example, leading to difficulty breathing or causing swelling of the throat). In their most severe form, food allergies can even cause anaphylaxis, a life-threatening condition in which the body goes into shock.

Recent data estimate that between 1.1 and 10.8% of the global population has a food allergy, and the rates of food allergies appear to be increasing. Documenting food allergies can be difficult, since food intolerances (less-serious adverse reactions to foods that are not allergies but may cause symptoms like gastrointestinal discomfort) are often mistaken for food allergies; self-reported food allergies are prone to bias; and the diagnostic process for identifying food allergies in patients varies between countries. In the United States, about 32 million people report having a food allergy, and each year around 200,000 people seek emergency medical care due to food allergies. Food allergies are particularly common in youth, with about one in every 13 children being diagnosed with a food allergy in the United States (and around 40% of children with food allergies being allergic to more than one food).

People who have asthma, who have suffered other allergic reactions, and/or who have a family history of food allergies may be more susceptible to developing a food allergy. Most food allergies are diagnosed in childhood, but around 15% of cases are first diagnosed in adulthood. Contrary to the popular belief that delaying the introduction of potential allergens to infants and toddlers can provide protection against an allergy, newer research finds the opposite holds true; in 2015, research from the Learning Early About Peanut Allergy (LEAP) study found that introducing potential allergens earlier and more frequently can lower the chances of developing a food allergy. The LEAP study was inspired by the observation that there was less prevalence of peanut allergies in Israel, where peanut products historically have been introduced early in infancy. By contrast, in the United Kingdom, where peanut introduction has been frequently delayed, there were ten times as many peanut allergy cases. The LEAP study found that infants who were introduced to peanuts early on were much less likely to have a peanut allergy compared with infants who avoided peanuts. This research changed the previous guidance about food allergen introduction; the current recommendation is to introduce food allergens around 6 months (and by 12 months) of age.

Although it’s been reported that more than 170 foods have triggered an allergic reaction, just eight major food allergens are responsible for almost all food-related allergic reactions in the United States. Recently, under the FASTER Act of 2021, the United States has also added sesame to the priority labeling list as the ninth major allergen. Ranging from most to least likely to cause a reaction in the general population, the list of major food allergens includes:

1. Milk
2. Eggs
3. Fish
4. Crustacean shellfish (e.g., crab, lobster, and shrimp)
5. Tree nuts (e.g., almonds, walnuts, and pecans)
6. Peanuts
7. Wheat
8. Soybeans
9. Sesame (effective January 1^st, 2023)

Other common allergens across the globe include cereals with gluten, sulfites, celery, lupin, and mustard, among others.

In the United States, the Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA) requires that these eight major allergens be clearly indicated on food labels. (Sesame will be included as the ninth major allergen starting January 1st, 2023). Ingredients derived from these allergens must also be listed on the label (e.g., wheat starch and soy lecithin), with the exception of highly refined oil. This additional information may be helpful for consumers removing these allergens, but the chance of these processing aids leading to an allergic reaction is fairly low.

Although gluten isn’t included on the list of major allergens in the United States, the Food and Drug Administration (FDA) has issued additional guidance for defining “gluten-free” on U.S. food labeling. The FDA also routinely examines additional allergens, ingredients, and additives to evaluate their health-risk impact and determine whether or not they require specific labeling. Research continues to emerge to support routine evaluation and potential additional labeling for gluten, certain additives (e.g., yellow 5, carmine, and sulfites), and other potential allergens.

Labeling food allergens varies across the world. For instance, the European Union identifies 14 allergens required to be listed on food labels. However, fermentation substrates and related products are exempt from these labeling laws. There have also been temporary exemptions for various food components, such as highly refined soybean oil, wheat starch hydrolysate, and fish gelatin. Additional research is underway to determine the allergenic potential of these ingredients before the European Union grants a permanent exemption.

If you’re concerned about a food allergy, it’s recommended that you undergo diagnostic testing from a board-certified allergist instead of self-diagnosing. Once a food allergy is confirmed by this specialized doctor, you can work with your medical team to reduce your exposure to the allergen—along with following these helpful safety tips:

1. Read ingredient lists on food labels: In the United States, as well as in many other countries, major allergens are required to be listed on the nutrition labels of packaged foods. If you are traveling, note that lists of allergens can vary between countries.
2. Before traveling, it’s recommended that you look up food labeling laws via your host country’s government website. In addition, some countries have travel tips on the International Food Allergy & Anaphylaxis Alliance website.
3. Be aware of inconsistent labeling: Know the alternative names for the allergen you’re avoiding. Be cognizant of imported products, since imported labels aren’t required to be labeled the same way as products manufactured in the United States. Certain labeling, including “egg-free” and “peanut-free,” isn’t regulated by the FDA.
4. Have medication on hand: Make sure your doctor has prescribed you enough medication (including an emergency EpiPen as needed) for you to manage your allergy every day, and have your medication with you any time you leave the house.
5. Back-up snacks: If you’re dining out and unsure about what foods on the menu contain allergens, you can always bring your own meal or supplementary snacks to ensure the food you’re eating is allergy-free.
6. Ask the waitstaff: Before ordering at a restaurant, ask the waitstaff if they can consult the chef about any potential allergens or cross-contamination.

This article was written by Debbie Fetter, PhD.