8 Most Common Food Allergies

A food allergy occurs when the body's immune system has an abnormal inflammatory response to a food. Most allergic reactions are mild, but they can also be serious and even fatal.

Common symptoms of a food allergy include itchy mouth, swollen tongue, hives or skin rash, watery eyes, runny nose, vomiting, diarrhea, and tightening of the throat. The most serious cases can result in anaphylaxis, a release of chemicals that sends the body into shock. 

When Do Food Allergies Develop?

Research suggests that 6.5% to 8% of American children and just over 10% of adults have food allergies.

According to the National Institute of Allergy and Infectious Disease (NIAID), no one is born with a food allergy. Researchers are still investigating why some people develop food allergies over others, but they believe genetics, family history, and age are all aspects of allergy development. Young children are more likely to develop a food allergy than older children and adults. 

If a healthcare professional suspects a food allergy, they will refer you to an allergist for testing. The allergist will conduct a blood or skin prick test to determine an allergy. Blood tests look for IgE, an antibody made by the body in response to the food allergy. Skin tests prick the skin with a small amount of the problematic food and wait for an allergic response. 

Although child allergies are common, research suggests that many children outgrow food allergies when they reach adolescence or adulthood.

Top Food Allergies

Be on the lookout for these most common food allergies. 

Peanuts

While they are often referenced as part of the nut family, peanuts are actually legumes and they differ from tree nuts. According to the NIAID, a 2010 national survey found that approximately 2% of American children had a peanut allergy.

Peanut allergy is the leading cause of death from food-induced anaphylaxis in the United States.

Two recent studies demonstrated the earlier children are introduced to peanuts, the less likely they are to form a serious allergy. Therefore, updated guidance recommends introducing peanuts early into a child’s diet. 

Milk

According to the American College of Allergy & Immunology, 2% to 3% of children younger than three have a milk allergy. About 80% of children will outgrow this allergy by the time they are 16. Milk allergies usually result in hives, upset stomach, vomiting, bloody stools, and sometimes anaphylaxis.

Children with a milk allergy must avoid milk in all forms. This includes all milk and dairy products, as well as “lactose-free” milk products. This also means avoiding foods with milk ingredients in them, such as milk chocolate.

Eggs

About 2% of children have an egg allergy, but close to 70% of them will outgrow it by the time they are 16 years old. The symptoms that accompany an egg allergy can range from a mild rash to anaphylaxis.

Those with an egg allergy must avoid any product containing eggs, as well as vaccines made with eggs.

Fish

Fish allergies may appear in adulthood, and they don’t necessarily translate to all fish. A person with a fish allergy may have a reaction to tuna, halibut, or salmon, while not having a reaction to shellfish, like crab, shrimp, and lobster.

Symptoms may range from mild to severe. Talk to an allergist about the types of fish to avoid. 

Shellfish

A shellfish allergy is usually exclusive to shrimp, lobster, and crab, and it's fairly common among adults, affecting nearly 7 million Americans. Many people with a shellfish allergy can safely eat mollusks (scallops, oysters, clams, and mussels).

Anyone with shellfish allergy symptoms should consult an allergist before eating any other kind of shellfish.

Shellfish and fish are often stored together at restaurants or in supermarkets, so cross-contamination is likely. Allergic reactions to shellfish can cause skin rashes, respiratory changes, gastrointestinal issues, and even cardiovascular events. Shellfish allergies most commonly appear in adulthood, but the condition can appear at any age.

Tree nuts

Tree nuts are different than peanuts and include walnuts, almonds, hazelnuts, pecans, cashews, and pistachios. An allergy to tree nuts is one of the most common among children and adults. It's also quite severe, with many reactions leading to anaphylaxis.

Wheat

A wheat allergy is common in children, but about two-thirds outgrow it by the age of 12. Although a wheat allergy is usually mild, some cases can be severe.

While many people with a wheat allergy can tolerate other grains, it varies from person to person. Wheat allergies are more common in families with a history of asthma and eczema.

Soy

Soy allergies are often hard to diagnose because the symptoms vary widely, from skin rashes to GI disturbances to cardiovascular symptoms. A person with a soy reaction may have different symptoms for each reaction. 

Food Allergy Safety

If you have a food allergy, follow these guidelines to stay safe: 

Read Food Labels

The Food Allergy Labeling and Consumer Protection Act of 2004 (FALCPA) states that manufacturers must identify the eight most common allergens in simple and clear language on a food label. The allergen should appear in the ingredients list, and the label may also contain a precautionary statement, such as "may contain," "might contain," "made on shared equipment" or "made in a facility with X food."

Recognize Specific Nuts

Since there are a large variety of nuts, make sure you can recognize and name each one as it appears in and out of the shell. Learn the types of foods that commonly contain nuts, such as granola bars, and read labels to look for cross-contamination from nuts that are processed in the same facility.

Speak to the Chef

When eating out, always make your allergy known and ask to speak with the chef. If the food allergy is severe, you may need to educate the restaurant on the need for separation surfaces. Call ahead to ensure that the facility can accommodate your needs. 

Always Carry an Epinephrine Pen

An allergist will prescribe an epinephrine pen after an allergy diagnosis. This is the first line of defense against anaphylaxis. Make a note of the expiration date on the pen and set a reminder to refill the prescription before it expires. If you experience shortness of breath, tightness in your throat, trouble breathing or swallowing, or other severe symptoms, reach for the epinephrine pen right away.