The 9 Most Common Food Allergies

Many foods can cause allergies, but some are more common than others. Almost 90% of all serious food allergies are related to proteins (allergens) in nine foods: milk, soy, egg, wheat, peanuts, tree nuts, fish, shellfish, and sesame.

These foods are often ingredients in other foods, so avoiding them requires diligence, including careful label reading and other measures. Even then, there may be times when exposures happen unknowingly.

This article covers what you need to know about the most common food allergies. It also lists some of the foods and products you'll need to avoid if you have these allergies

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Watch Now: 8 Surprising Sources of Common Food Allergens

Food Allergy Symptoms

Food allergy symptoms can range from a mild rash to a severe, life-threatening reaction called anaphylaxis. Some food allergies are commonly outgrown, while others are typically lifelong.

Symptoms can vary from person to person and, in some cases, from episode to episode in the same individual. Even if you have a mild allergic reaction the first time, it can be severe or life-threatening the next.

Most Common Food Allergies - Illustration by Jiaqi Zhou

Verywell / Jiaqi Zhou

Symptoms tend to begin anywhere from a few minutes to an hour or so after you have eaten a food you are allergic to.

The most common food allergy symptoms include:

  • Swelling and itching of the lips and mouth
  • Tightness in the throat or hoarse voice
  • Nausea and vomiting
  • Diarrhea and cramps
  • Itchy, raised bumps (hives)
  • Swelling of the skin
  • Itchy skin

Anaphylaxis is the most severe form of an allergic reaction. It causes systemic symptoms, meaning that symptoms involve multiple systems of the body.

Symptoms of anaphylaxis include:

  • Trouble breathing or wheezing
  • Feeling as though your throat is closing
  • Swelling of the lips or tongue
  • Flushing of the skin
  • Itching of the palms or soles of the feet
  • Feeling faint
  • Nausea, vomiting, stomach pain
  • Fast pulse
  • Low blood pressure
  • Loss of consciousness

Anaphylaxis is life-threatening. Call 911 at the first sign of anaphylaxis. Do not wait to see if symptoms get better.

Anaphylaxis is treated with epinephrine in the form of an auto-injector, such as an EpiPen or AUVI-Q. If you have been prescribed one for a severe food allergy, carry it with you at all times and use it at the first sign of anaphylaxis.

When to Seek Medical Attention

If you have a severe allergic reaction—trouble breathing, swelling in the mouth, or symptoms that affect more than one system in the body (like hives and stomach pain)—call 911 and go to the ER.

Cow's Milk

When you have a milk allergy, your immune system overreacts to the proteins in milk—casein and whey. This condition is different than lactose intolerance, which is the inability to properly digest sugar lactose. 

Milk allergy is the most common food allergy among children. Around 20% of American children with a food allergy are allergic to milk, and nearly one-third of them have a severe allergic reaction to it at some point.

Although some research is conflicting, it appears that many children (about half) outgrow milk allergy by the time they are five years old. About 75% can tolerate milk proteins by the time they are teenagers.

Some problematic foods are obvious, like milk, cheese, and ice cream. With other foods or dishes, it’s hard to know whether they contain milk unless you read product ingredient lists or, if you're at a restaurant, speak to the chef.

According to the Food Allergen Labeling and Consumer Protection Act (FALCPA), food allergens must be identified on food labels in plain, easy-to-understand language.

If the food has milk in it, the ingredient list should say “contains milk.” If the ingredient is a milk product, it could be listed in parentheses—for example, “whey (milk).”

Ingredients that people with milk allergies should avoid include:

  • Casein
  • Buttermilk
  • Cream
  • Diacetyl
  • Ghee
  • Lactose
  • Whey

In addition to milk and dairy products, milk proteins can be found in some unexpected places, such as:

  • Artificial butter flavor
  • Non-dairy creamer
  • Deli meats
  • Hot dogs
  • Canned tuna

Eggs

People who are allergic to eggs are triggered by the proteins in eggs. You can be allergic to the egg white, the egg yolk, or both. Experts recommend avoiding the whole egg when you have an allergy. 

About 2.5% of all children have an egg allergy, making this the second most common food allergy in kids. Diagnosis typically happens before age two. About half of these children will outgrow their allergy by age 5, and most will outgrow it by adolescence.

According to FALCPA guidelines, eggs must be listed on food labels in plain language, such as “contains egg." Always read the ingredient label for evidence of egg in a food product.

Be aware of hidden egg ingredients in such foods as:

  • Liquid egg substitutes
  • Pasta
  • The foam topping of some specialty coffee drinks
  • Breaded and batter-fried foods
  • Caesar salad dressing
  • Crepes and waffles
  • Lollipops and other candies
  • Mayonnaise
  • Meatloaf and meatballs
  • Sauces, such as Hollandaise and tartar sauce
  • Wine (egg whites may be used during the production process)

Egg protein also may be present in vaccines, such as those for the flu and MMR (measles, mumps, and rubella). If you have an egg allergy, talk with your healthcare provider about the risks and benefits of getting vaccinated.

Peanuts

A peanut allergy is often considered a life-threatening allergy because the rates of anaphylaxis are higher than those of milk, egg, or wheat allergies.

Peanuts are part of the legume family, which includes soybeans, peas, lentils, and beans. The protein in peanuts is similar to tree nuts, so if you have a peanut allergy, you’re more likely to have a tree nut allergy and vice versa.

Being allergic to peanuts does not mean that you are allergic to other legumes such as soybeans, peas, and lentils. However, allergy to lupin (another legume) can occur in those with peanut allergies.

Peanuts are one of the most common foods to cause allergies. The number of cases has increased in recent years. A 2017 research study presented at the American College of Allergy, Asthma and Immunology (ACAAI) Annual Scientific Meeting reported that peanut allergies had increased 21% since 2010. The study found that 2.5% of U.S. children are allergic to peanuts.

For most people, peanut allergies are lifelong.

Even a small amount of peanut protein can cause an allergic reaction, so it’s important to read labels carefully and ask questions about ingredients. Look for "contains peanut" or “made on shared equipment with peanuts” on food labels. 

Baked goods and candy are high-risk foods for those with peanut allergy. Even if these items don’t contain peanuts, cross-contamination where they are made is a strong possibility. Cross-contamination is also a notable concern in African, Asian, Mediterranean, and Mexican restaurants, which often prepare meals with peanuts. 

Peanuts can also be found in surprising places, such as:

  • Chili sauce
  • Chili and soups
  • Grain breads
  • Cake icing
  • Cereals and granola
  • Pancakes
  • Pesto
  • Egg rolls
  • Salad dressings
  • Sunflower seed butter
  • Ice cream

If you or your child has a peanut allergy, make sure you read food labels before using any products. Always ask questions at restaurants, even if you have before and think a food or dish is safe. Changes in ingredients and preparation processes can happen at any time, putting you at risk.

Soybeans

People who are allergic to soy have a reaction to the proteins in soybeans. Allergic reactions are usually mild, but as with all food allergies, it is possible to have a severe, life-threatening reaction.

Soy is a common food allergy for children but is less so for teens and adults. About 0.4% of children are allergic to soy. It’s estimated that 50% of kids outgrow a soy allergy after one year, and most will outgrow it by age 10.

Soy must be labeled on food packages. Food and drinks with soy include:

  • Infant formula
  • Edamame
  • Miso
  • Tempeh
  • Tofu
  • Canned tuna
  • Low-fat peanut butter
  • Sauces

Because soy is a staple in many popular vegetarian dishes, particularly those that include tofu, vegetarians with a soy allergy will need to rely on other protein sources.

Wheat

A wheat allergy is caused by an allergic reaction to a wheat protein. It’s sometimes confused with celiac disease, even though they are two different conditions. Celiac disease is an autoimmune condition in which eating gluten can cause damage in the small intestine. Gluten is not usually involved in wheat allergy reactions.

Wheat allergies are common in children but rare in adults. About 0.4% of children in the U.S. are allergic to wheat. Two-thirds of children will outgrow a wheat allergy by age 12.

Some children who are allergic to wheat are allergic to other grains as well, although many can substitute other types of grains to cover their nutritional needs. Check with your allergist if other grains like amaranth, barley, or rye are safe to eat. 

If you have a wheat allergy, check all food labels, even if you think the food doesn't contain wheat.

Wheat can be found in the following:

  • Breads
  • Cereals
  • Pasta
  • Crackers
  • Beer
  • Candy
  • Soy sauce
  • Deli meats
  • Ice cream
  • Imitation crabmeat

Tree Nuts

Tree nuts include a broad range of nuts, including:

  • Walnuts
  • Pecans
  • Pistachios
  • Hazelnuts
  • Almonds

If you’re allergic to one tree nut, you’re more likely to be allergic to more than one. The risk of an anaphylactic reaction to tree nuts is higher than it is for milk, egg, or wheat.  

About 0.8% of children and 0.6% of adults have a tree nut allergy. For people with peanut allergies, about 25% to 40% also have a tree nut allergy.

Tree nut allergies can present for the first time in both children and adults. It’s usually a lifelong allergy, but about 9% of children with a tree nut allergy will outgrow it. 

Your healthcare provider may recommend that you avoid all tree nuts and peanuts because of the risk of cross-contamination. Food labels must list the type of tree nut in the ingredient list. There are many names for different types of tree nuts, so talk with your healthcare provider about the ones you should avoid. 

Tree nuts can be found in such foods as:

  • Cereals
  • Crackers
  • Cookies
  • Candy
  • Chocolates
  • Pesto
  • Barbecue sauces
  • Deli meats

Fish

When you have a fish allergy, you’re allergic to the proteins in finned fish, such as tuna, cod, halibut, and salmon. A fish allergy is different than a shellfish allergy, so you may have one but not the other.

The allergic reaction is usually caused by eating fish, but some people also have symptoms after touching it or breathing in vapors while fish is being cooked.

About 0.2% of children and 0.5% of adults have a fish allergy. While it can develop during childhood, it can also first occur in adulthood. People who have fish allergies usually don’t outgrow them.

It is possible to be allergic to one type of fish species and not others. Salmon, tuna, and halibut are the most common problematic fish for people with fish allergy. However, more than half of people who are allergic to one type of fish are allergic to others, so your healthcare provider may advise you to avoid all fish to be safe.

According to FALCPA, the specific type of fish included in a food product must be stated on the package.

Fish has been found in surprising foods, such as:

  • Caesar salad dressing
  • Artificial seafood
  • Worcestershire sauce
  • Barbecue sauce
  • Kosher gelatin, which is made from fish bones

Avoid eating at seafood restaurants, where there is a risk of cross-contamination, even if you order a non-fish meal. If a restaurant (even a non-seafood one) serves fried fish, avoid ordering foods like French fries that may be cooked in the same oil. 

Shellfish

There are two types of shellfish: crustaceans (shrimp, crab, and lobster) and mollusks (clams, oysters, mussels, and scallops).

Allergic reactions are usually caused by crustacean shellfish and tend to be severe. The reaction is usually caused by eating the shellfish, but it may also be caused by touching it or breathing the steam from cooking shellfish.

Shellfish allergy occurs in adults more often than children, with about 60% having their first reaction as an adult. About 2% of adults report having an allergy to crustacean shellfish. Once you have a shellfish allergy, it tends to be a lifelong.

The specific crustacean shellfish must be labeled as an ingredient on packaged food, according to FALCPA. Mollusks are not considered a major allergen and may not be fully disclosed on a product label.

As with fish allergy, it is best to avoid seafood restaurants due to concerns with cross-contamination. If you find yourself dining in one, do your best to avoid a reaction by speaking to the staff and insisting that your food not be prepared or cooked in an area shellfish has touched.

Some unexpected places you may find shellfish include glucosamine (a supplement) and seafood flavoring.

Sesame

Sesame wasn't officially considered a major food allergen until the Food Allergy Safety, Treatment, Education, and Research (FASTER) Act became law in 2021. The act recognized sesame as the ninth major food allergen.

FASTER ensured that food manufacturers must list sesame on product labels when it is used as an ingredient, according to FALCPA guidelines. Food labels must be modified to include sesame by January 1, 2023.

About 17% of children with food allergies are allergic to sesame, and only 20% to 30% of children outgrow their sesame allergy. Like the other major allergens, when a person is allergic to sesame, they are allergic to the proteins in sesame that trigger an immune reaction.

Sesame is a key ingredient in many international cuisines, such as Chinese, Japanese, Middle Eastern, African, and American foods. It is typically used to add flavor, either as a topping or as a cold-pressed cooking oil.

Foods that often have sesame or sesame oil in them include:

  • Asian cuisine (sesame oil is commonly used for cooking)
  • Baked goods, such as hamburger buns, bagels, breads, and muffins
  • Bread crumbs
  • Cereals, such as granola and muesli
  • Chips and crackers
  • Dipping sauces, such as tahini, hummus, and baba ghanoush
  • Dressings, gravies, and marinades
  • Falafel
  • Flavored rice, noodles, risottos, and stir fry
  • Processed meats and sausages
  • Protein and energy bars
  • Sushi and tempeh
  • Halva

Be aware of cross-contamination with sesame, particularly in Asian restaurants. It may be best to avoid Asian cuisine if you have a sesame allergy.

Tests for Food Allergies

If you think that you or your child may have a food allergy, make an appointment with your healthcare provider. Taking note of food allergy symptoms and when they occur can help in the diagnostic process.

In some cases, allergy tests may be done in your healthcare provider's office. Or, your provider may refer you to an allergist (a physician who specializes in diagnosing allergies).

After discussing your medical history, the provider will likely proceed with either a skin test or a blood test. When done correctly, both tests can help your provider diagnose whether or not you are allergic to any of the nine major allergens.

Neither a skin or blood test can predict how severely you will react to a food when you eat it. In fact, it's not uncommon for a person to test "allergic" to a food, then have no symptoms when they eat that food. Both skin and blood tests are more helpful for ruling out foods that you are not allergic to.

Skin Testing

An allergist can conduct a skin prick test in their office and get the results back within 30 minutes. The allergist will prick a small area on your arm or back with a sterile probe that contains a tiny amount of the food allergen. The test isn't painful, though it can feel a bit itchy.

The results are positive if you develop a wheal—which looks like a mosquito bite—where the skin was pricked. How big or small the wheal is varies from person to person. Its size does not necessarily predict how severe your allergic reaction to that food would be if you ate it.

Blood Testing

Blood tests measure the amount of immunoglobulin E (IgE) antibodies in your blood when you are exposed to the allergen in question. You might also hear this test referred to as an immunoassay test.

For the blood test, your healthcare provider will use a small needle to take a blood sample from your arm. Blood tests are not as sensitive as skin prick tests, and it can take days to weeks before the results come back.

Your provider may order a blood test instead of a skin prick test if you cannot tolerate the needle prick required for a skin prick test. You may also need a blood test if there is a chance that you could have a severe allergic reaction to the tiny amount of allergen used in the skin prick test.

Oral Food Challenge (OFC)

Also called a feeding test, an OFC is a test in which a food is eaten very slowly, in gradual amounts. The test is done under the supervision of a healthcare provider; it's not something you should ever attempt at home.

An OFC tends to be done after a skin prick test or blood test to confirm a food allergy diagnosis. If there is any question about whether or not you are allergic to a food, the OFC will likely provide an answer.

The test lasts a few hours. During the first hour, your provider will give you gradually increasing portion sizes while watching for any signs of an allergic reaction. After this first hour, your provider will monitor you for signs of an allergic reaction for another one to three hours.

Your healthcare provider may ask you not to take any antihistamines for three to five days before your allergy test. Antihistamines are medications used to treat mild allergic reactions. Taking them in the days before your allergy test could interfere with the accuracy of your results.

Summary

Cow's milk, eggs, peanuts, soybeans, wheat, tree nuts, fish, shellfish, and sesame are responsible for the majority of food allergies. Food allergy symptoms range from mild and comfortable to life-threatening anaphylaxis.

If you suspect you have a food allergy, your healthcare provider will conduct a skin prick test or blood test and possibly an oral food challenge to determine which food(s) you are allergic to.

A Word From Verywell

If your healthcare provider prescribes an epinephrine auto-injector, such as an EpiPen or AUVI-Q, it is crucial that you keep it with you at all times. Anaphylaxis can occur within seconds to minutes after you have been exposed to a food you are allergic to, so you need to be ready.

Even if you have never needed to use an auto-injector on yourself or on a child, it's important to know when and how to use it. If you have an EpiPen, use the EpiPen trainer device to practice as often as you need to feel confident.

Frequently Asked Questions

  • Can you develop food allergies as an adult?

    Most food allergies start in the first two years of life, but it's also possible for adults to develop an allergy to a food they previously ate with no problem.

  • Is it possible to outgrow food allergies?

    Children are much more likely than adults to outgrow a food allergy. About 80% of people who are allergic to egg, milk, and/or wheat allergies outgrow them, usually by the time they are 16. Allergies to tree nuts, fish, and shellfish tend to be lifelong.

  • How do you treat an allergic reaction?

    Epinephrine is the first-line treatment for anaphylaxis. If you have been prescribed an EpiPen or AUVI-Q auto-injector, use it at the first sign of an allergic reaction, then call 911. If you have not been prescribed an auto-injector, you can treat a mild allergic reaction by taking an antihistamine.

12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Jill Castle, MS, RD
Jill Castle, MS, RD, is a childhood nutrition expert, published book author, consultant, and public speaker who helps parents nourish healthy kids.