What You Didn't Know About The Top Allergens: 15 Facts That May Surprise You

9 food groups are responsible for around 90% of all food allergies in the United States. Read on for 15 more surprising facts about these top allergy-causing foods.

These foods are:

  • Milk
  • Egg
  • Peanut
  • Tree nuts
  • Wheat
  • Soy
  • Finned fish
  • Shellfish
  • Sesame

We’ve rounded up 15 more facts about these top 9 allergy-causing food groups that will probably surprise you. Read on to find out what you didnt know about the top allergens.

1. 80% of food allergies in young children are allergies to peanut, egg, and milk.

Milk, egg, and peanut allergies are the three most common food allergies in babies and young children. According to one study by Dr. Ruchi Gupta, around 80% of food allergies in children age 5 and under are to these three foods.

2. The amount of peanut allergies has spiked in recent years.

Peanut allergies, in particular, have become more and more common. In recent years, the prevalence of peanut allergy in children has more than tripled in the US.

3. If someone has a peanut allergy, they may be more likely to develop a tree nut allergy.

Tree nut allergies are a completely different allergy category from peanut allergies. After all, peanuts are legumes that grow in the ground, not nuts that grow on trees. But peanut allergies and tree nut allergies still seem to be closely connected. 30% of people with peanut allergies are also allergic to tree nuts.

4. Certain tree nut allergies tend to show up together.

When someone develops an allergy to one tree nut, they may be more likely to develop an allergy to a closely related tree nut. This is known as cross-reactivity.

Cross-reactivity happens because the proteins in certain tree nuts are very similar to each other. Cashews and pistachios have similar proteins, and pecans and walnuts have similar proteins.

Typically, when someone has a food allergy, their immune system produces antibodies that react to very specific food proteins. But since some tree nut proteins are so similar, the immune system of someone with a certain tree nut allergy may start to treat two proteins exactly the same. This may cause an allergic reaction when their immune system detects the proteins from either closely related tree nut.

Even when cross-reactivity comes into play, though, most people with tree nut allergies are allergic to only 1 or 2 types of tree nuts, and may be able to safely eat other types of tree nuts.

5. Milk and peanut allergies are the most common causes of allergic reactions in schools.

According to one study, milk is responsible for 32% of food allergic reactions in schools. Meanwhile, peanut is responsible for 29% of food allergic reactions in schools.

6. Wheat allergies are not the same as gluten intolerances.

Wheat allergies are different from gluten intolerances, and there is no such thing as an allergy to gluten.

A wheat allergy causes someone’s immune system to respond to a protein specifically found in wheat. Meanwhile, gluten intolerances cause immune system responses to gluten, a protein that can be found in many grains.

Even though gluten is present in wheat, it also shows up in multiple other grains, including rye and barley. So, it isn't a specific food protein.

Board Certified Allergist, Dr. Katie Marks-Cogan, shares more information on gluten intolerance:

7. Wheat allergies can cause allergic reactions to some cosmetics.

People with wheat allergies can develop allergic reactions to cosmetic products with wheat in them, if these products touch their lips. But wheat doesn’t have to be clearly listed on cosmetic product labels, so wheat allergy families have to read cosmetics labels very carefully.

8. Soy allergies and peanut allergies aren’t related.

Soybeans and peanuts both belong to the legume family. Even so, a soy allergy doesn’t make someone more likely to develop a peanut allergy, and a peanut allergy doesn’t make someone more likely to develop a soy allergy.

9. Finned fish allergies tend to be adult allergies.

Around 40% of people with a fish allergy had their first allergic reaction to fish as adults.

And as a study led by Dr. Scott Sicherer reports, fish allergies are more common in adults than children, and far more common in children ages 6-17 than in young children ages 0-5.

In addition, fish allergy is far less common in young children than allergies to peanut, egg, and milk.

10. Shellfish allergies are also more common in adults.

Around 60% of people with any allergies to shellfish have their first shellfish allergic reaction as adults.

Also, shrimp allergy, one of the more common shellfish allergies, only affects ~1% of children. Meanwhile, the three most common childhood food allergies (peanut, egg, and milk allergies) affect ~7% of children.

11. Shrimp allergies are less severe in children than in adults.

Results of one study reported by the AAAAI show that a severe reaction from shrimp allergies is much rarer in children than in adults. As the study reports, "anaphylaxis caused by shrimp allergy in adults is 44 percent," but "in children [it] is only 7.8 percent." Children with shrimp allergies usually have mild to moderate allergic reactions, not severe ones.

12. If someone has a sesame allergy, they probably have another food allergy.

Around 80% of people with sesame allergies have at least one other food allergy. This means that someone who already has another food allergy is more likely to develop sesame allergies.

According to another study, sesame allergies often specifically develop alongside peanut allergies and tree nut allergies in children. So if someone has a peanut or tree nut allergy, they may be at increased risk for a sesame allergy.

13. Sesame allergies are common, but sesame doesn’t have to be listed on food labels.

Sesame is the ninth-most common food allergy. It is estimated to affect over 1.5 million people in the United States.

But sesame isn't required to be listed clearly on ingredient labels, because sesame isn't counted as or regulated like one of the top 8 allergens affecting Americans. This can make it very difficult for people with sesame allergy and their families to identify the foods that contain sesame, and that could cause an allergic reaction.

Even worse, sesame may also appear in spice blends and flavorings without being listed as an ingredient.

14. Children are more likely to “outgrow” some of the top food allergies than others

Peanut, tree nut, and sesame allergies tend to be lifelong. Only around 20% of children with peanut allergies eventually "outgrow" them, and only 20-30% of children with a sesame allergy will "outgrow" that allergy. Tree nut allergies are even less likely to be outgrown.

Fish and shellfish allergies also tend to be lifelong, but as we mentioned above, they usually develop in adulthood.

Children are more likely to "outgrow" their milk, soy, wheat or egg allergy.

15. The USDA recommends “introduce infants to potentially allergenic foods.”

In the 2020-2025 USDA Dietary Guidelines, the USDA recommends “potentially allergenic foods (e.g., peanuts, egg, cow milk products, tree nuts, wheat, crustacean shellfish, fish, and soy) should be introduced when other complementary foods are introduced to an infant’s diet.” These guidelines help provide recommendations for parents to give their children a healthy start and tp make evidence-based food and beverage choices for their families.

Introduce Allergens Safely and Easily with Ready. Set. Food!

All health-related content on this website is for informational purposes only and does not create a doctor-patient relationship. Always seek the advice of your own pediatrician in connection with any questions regarding your baby’s health.

These statements have not been evaluated by the Food and Drug Administration. Products are not intended to diagnose, treat, cure or prevent any disease.  If your infant has severe eczema, check with your infant’s healthcare provider before feeding foods containing ground peanuts.