Food Allergies & Symptoms

Food allergies are a growing health concern affecting millions of people worldwide. They occur when the immune system reacts abnormally to certain proteins found in specific foods. While some food allergies can be mild, others can be severe and life-threatening. It is crucial to understand common food allergies to identify potential triggers, manage symptoms, and ensure the safety of individuals with food allergies.

Everything You Need to Know About Common Food Allergies

Discover the most common food allergens and their symptoms. Learn how to avoid them, and get tips on managing food allergies.

This article is based on reporting that features expert sources.

U.S. News & World Report

The Top Food Allergies to Look Out For

About 32 million people – including 6% of children – experience food allergies in the United States, according to the Centers for Disease Control and Prevention.




Despite the high prevalence of these allergies, the U.S. isn’t exactly allergy-proof. From trying mystery sauces at restaurants to cross contamination in a school cafeteria or a first kiss after a dinner date – the risk of exposure to allergens is everywhere.

Even small – or trace – exposures to the food people are allergic to can lead not only to symptoms like itching and skin rash, or hives, but swelling of the face and throat, as well as difficulty breathing. In the most severe instances, an allergic reaction can be fatal.

Given the seriousness of food allergies, it’s important to heed any of a broad range of possible symptoms after food is consumed, and seek medical attention for adults or kids to ensure proper diagnosis and allergy management. Here’s what to know about common food allergens – and how to stay safe if allergic to them.




How Many Major Food Allergens Are There?

The Food and Drug Administration designates nine foods as the most common food allergens:

Typically, protein is the cause of a food allergy. For milk, that’s cow’s milk protein – casein and whey. Cow’s milk is the most common allergy in infancy and childhood. Foods to avoid: milk and all milk products (yogurt, cheese, cottage cheese, sour cream), butter, milk powder, custard and chocolate. Pay particular attention to processed grains that may contain a milk derivative, such as casein and whey. Note that a milk allergy differs from lactose intolerance, which is a problem digesting the sugar (lactose) in milk.

Both egg whites and egg yolks contain the protein that can cause allergies, but an allergy to egg whites is most common. However, since it’s impossible to separate the white and the yolk without any cross-contamination, you must avoid eggs as a whole. Foods to avoid: eggs, of course, but also albumin, mayonnaise and meringue. Ice cream and many baked goods also contain eggs, as well as other foods where eggs are often a hidden ingredient, such as salad dressings and meatballs.

Fish – or specifically finned fish such as tuna, halibut or salmon – is another common food allergen. Even cooking fish, such as sauteing on your stove – which can aerosolize the protein – can impact someone with a fish allergy. Fish is a common ingredient in Worchestershire sauce, Caesar salad and many Asian dishes that use fish-based stock.

Shellfish allergy is the most common food allergy in adults. Shellfish in all forms (shrimp, crab lobster, mussels, scallops, etc.) should be avoided, as well as any foods containing these products. Often, people with shellfish allergies can’t even be in the same vicinity as the shellfish or they’ll react.

Tree nuts include almonds, cashews, walnuts, Brazil nuts, hazelnuts, chestnuts, macadamia nuts, pecans and pistachios – as well as any nut butters or other foods containing these nuts, such as pralines and other candies. Along with peanuts and shellfish, tree nut allergies are among the food allergies most frequently linked with anaphylaxis – the rapidly occurring allergic reaction that can kill. Besides avoidance of the allergen, it’s recommended people carry epinephrine – which can reverse life-threatening effects like a dangerous drop in blood pressure during anaphylaxis – or other allergy medications to manage an unexpected allergic reaction.

Peanuts are the most severe allergy for children. This legume can cause an anaphylactic reaction from even a small amount of exposure; therefore, children need to be very careful not to consume any product that even has a trace amount of peanuts or peanut butter. Peanuts can be used in many food items, so it’s important to read the ingredients list for all foods if your child has a peanut allergy.

Wheat allergy is different from celiac disease. Wheat is found in many foods, such as cereals, pastas, crackers and ice cream. Other foods to avoid: flour, couscous, farro, bread crumbs, bulgur, seitan, semolina and food starch.

Soybeans are a member of the legume family, but that doesn’t mean you’re automatically allergic to other legumes. Foods to avoid: soybeans, soy milk, tofu, edamame, miso, soy protein and soy sauce. Pay particular attention to granola bars, energy drinks, baked goods and foods that may have added soy.

In January 2023, sesame became a new addition to the list of top allergens. The edible seeds are found in hummus, tahini, sushi, hamburger buns, bagels, energy bars, sesame oil and certain spice blends.

Daily Contact With Common Food Allergens

For people with food allergies, avoiding allergic reactions isn’t easy. Things like cross contamination, wrongly or vaguely labeled food items, aerosolized contact and indirect contact with others consuming the allergen nearby increase levels of risk every day.

The FDA requires food distributors to visibly label products that contain, or “may contain” the nine most common allergens. However, that “may contain” label doesn’t offer much guiding information.