Fish and Wheat with an X through them due to allergies

Food Allergies

Food allergies occur when your body mistakenly identifies and treats an ingested food as a threat, initiating an immune system response. Even eating a tiny amount of the offending food can trigger an allergic reaction, which may involve anything from hives to eczema, stomach troubles to difficulty breathing, and even death.

Some allergies may be lifelong, while others may fade over time. More than 90% of the most common food allergies are caused by one of eight allergens: dairy, eggs, wheat, soy, peanuts, tree nuts, fish, or shellfish.

Overall, food allergies are relatively common, impacting 32 million Americans, including 5.6 million children under the age of 18. While food allergies tend to run in families, doctors are not able to predict who will develop food allergies and who will not.

Frequently Asked Questions

  • What's the best way to test for food allergies?

    Food allergies can be diagnosed via a combination of different methods: a blood test (IgE antibody test, known as immunoCAP or ELISA), a skin prick test, an elimination diet, or an oral challenge test. An oral challenge is often used when other testing is inconclusive, as it's the only test that can be used to actually confirm a food allergy, or to test if a food allergy has been outgrown.

  • What causes food allergies?

    Food allergies are caused by an immune system overreaction to a food the body has mistakenly deemed harmful. Experts aren't entirely sure why some people develop allergies and others don't. Environmental factors may play a role, as may family history. Having eczema, allergic rhinitis, or asthma makes you much more likely to have a food allergy, a phenomenon known as atopy.

  • Are food allergies genetic?

    Genetics seem to play a big role in the development of food allergies, as having a parent/sibling with a food allergy or atopy (allergic rhinitis, asthma, or eczema) can greatly increase your chances. But genetics aren't the only factor. Environmental triggers, such as where you live and the regional cuisines you regularly eat, are also a big component in development.

  • How long does an allergic reaction to food last?

    Allergic reactions may vary in length. Some allergic reactions may set in a few minutes after consuming the allergenic food, whereas others may appear up to two hours later. If hives or a rash develop, they may take a day or two to fully clear up. If you're experiencing any symptoms of anaphylaxis, such as throat constriction, dizziness, or shock, seek immediate medical help.

  • Can food allergies cause a fever?

    While food allergies can sometimes cause cold- and flu-like symptoms such as runny nose, sore throat, or sneezing, they do not typically cause a fever. Allergic rhinitis, also known as hay fever, is a common allergy, but it doesn't cause a fever.

  • Can food allergies cause acne?

    Food allergies are unlikely to cause acne, however, acne may be related to a food intolerance or sensitivity. A food intolerance is a condition in which the body has a reaction to a certain food, but not an immune response.

Key Terms

Photo composite of small servings of common allergens like nuts, soy beans, shrimp and milk
The Best At-Home Food Sensitivity Tests of 2021
Kiwi
Why You Might Be Allergic to Kiwis
A woman adding sugar to her drink
Sugar Intolerance or Sugar Allergy?
Bowl of emmer wheat
Wheat Allergy and Gluten Intolerance: Not the Same!
hand shucking oysters mollusk shellfish over ice
Everything You Need to Know About Shellfish Allergies
Bowl of hazelnuts
Are You Allergic to Hazelnuts? Learn About Common Signs and Treatment
Bowls of goldfish, cheetos, and graham crackers
Is Annatto Safe If You're Allergic to Nuts?
Cinnamon
Could You Be Allergic to Cinnamon?
Group of friends toasting with drinks
How Some Food Allergies Can Affect Your Ability to Drink Alcohol
A man pouring a glass of red wine
Learn the Symptoms, Diagnosis, and Treatment of Histamine Intolerance
Chocolate candies
Is There Really Such a Thing as an Allergy to Chocolate?
Bowls of beans, nuts, quinoa, and flaxseed
Food Choices for a Soy-Free Diet
Close-Up Of Brown Eggs Against Black Background
What to Do If You Think You Could be Allergic to Eggs
Symbols of the most common food allergies. Ideal icons for menus, classrooms, newsletters, lunchrooms.
Crash Course on the Most Common Food Allergens
Bowls of various nuts
Tree Nut Allergy Diet Guide
hands breaking wheat stalks in half
Overview of Gluten Allergy
peanut allergy
What You Should Know About Peanut Allergies
Child drinking milk
Could Your Child Have a Milk Allergy?
Various food intolerance include red wine, bread, and ice cream
What Really Happens to Your Body When You Have a Food Intolerance?
red-snapper-on-ice-by-John-Kuczala:GettyImages.jpg
Here's How to Cope If You're Allergic to Fish
upset child with food
Eosinophilic Esophagitis: Part Food Allergy, Part Swallowing Disorder
woman staring wistfully at food
Why Faking a Food Allergy is Bad
Girl gasping while baking
Code Words for Milk Ingredients If You Have an Allergy
serve-yourself yogurt bar - cross-contamination risks
How to Reduce Cross-Contamination If You Have Food Allergies
White chocolate
Find out If You Can Eat White Chocolate With a Chocolate Allergy
peanut allergy
23 Non-Food Items You'd Never Guess Would Contain Peanuts (But Can)
Coconut split and shavings
How to Cope If You're Allergic to Coconut
Bowl of yogurt with granola and raspberries
What You Should Know About Lactose Intolerance
FangXiaNuo / GettyImages
Baby Formula Allergy: Causes, Symptoms, and How to Treat It
Kids washing hands in classroom
How to Clean Schools Properly to Eliminate Peanut Residue
Person feeding a baby in a high chair
How You Can Help Prevent Food Allergies From Your Baby
Determined girl refusing to eat.
Helping Children With Texture Aversions to Food
Boy not wanting to eat.
Possible Medical Reasons Your Child Isn't Eating
Baby feeding
When Your Baby Might Need Hypoallergenic Formula
Boy eating with a fork and making a face
Children Who Gag When Eating Can Have Medical Problems
Portrait of boy, scratching his cheeks
The Pros and Cons of Creating a 504 Plan for Your Child's Food Allergy
child picky eater
Discover When It's Time to Be Concerned If Your Child Is a Picky Eater
Two young boys at school playing with fruit and being silly
My Child's School Is Peanut-Free, So What Can I Send for Snacks?
Baby girl feeding on milk with a milk bottle
What You Should Know About Milk and Dairy Allergies
Cup of milk
When Might My Child Outgrow His Milk Allergy?
Peanut butter and jelly sandwich in lunchbox
Is Banning Peanuts From Schools for Allergies the Right Way to Go?
Woman writing letter on couch at home
Writing Other Parents About Your Child's Food Allergy
Children's allergic skin test for child's hand. Laboratory at the Allergy clinic. Clinical study. Close-up photo, selective focus
Allergy Testing for Children
baby eating from spoon
Does Your Baby Have a Food Allergy?
a young child wearing a paper crown
Treat Ideas for Schools With Non-Food Policies of Celebrations
Blueberry muffins
8 Surprising Signs You May Have a Gluten Sensitivity
Iced coffee with milk
Caffeine Allergy: Symptoms, Causes, Diagnosis, and Treatment
Bowl of ice cream, cut cantaloupe, and sour gummy candies
Could Your Odd Symptoms Mean You're Allergic to Citric Acid?
Iced coffee with milk
How Common Is a Coffee or Caffeine Allergy?
Woman selecting fruit at grocery store
Why Do Raw Apples Cause Your Mouth to Itch?
Woman shopping in grocery store aisle
Is Your Food Making You Sick? Try an Allergy Elimination Diet
Various chopped fruit and vegetables
Fruit and Vegetable Allergies Symptoms and Diagnosis
Toddler girl holding glass of milk
Milk Allergy
MSG Allergies
Why Reactions to MSG Aren't Really Allergies
Close-up shot of a woman suffering from a headache and rubbing her temples at home
How Allergies Can Make You Dizzy
Food Allergies
When Are Your Food Allergy Symptoms an Actual Medical Emergency?
Children sticking out tongues dyed red and blue from their ice pop during Fourth of July parade
What You Need to Know About the Color Dye Allergy
Popcorn, chips, doritos, starburst, m&ms, sourpatch gummies
The Potential Risks of Tartrazine
Various spices on rack
How to Tell If You Have a Spice Allergy
Salmon
How a Fish Allergy From Other Types of Food Allergies
Page 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.
  1. Food Allergy Research and Education (FARE). Facts and statistics.

  2. American College of Allergy, Asthma, and Immunology. Food allergy diagnosis. Updated February 12, 2019.

  3. Weidinger S, Novak N. Atopic dermatitis. Lancet. 2016 Mar 12;387(10023):1109-22. doi:10.1016/S0140-6736(15)00149-X.

Additional Reading