Food Allergies
Symptoms, Causes, Treatments, Questions & Related Topics

Possible Symptoms for Food Allergies

  • Hives
  • Wheezing
  • Hoarse voice
  • Swollen eyelids, face, lips, and/or tongue
  • Breathing difficulty
  • Trouble swallowing
  • Swollen throat
  • Swollen lips
  • Itching anywhere on the body, especially on the mouth, throat, eyes, and skin
  • Lightheadedness
  • Fainting
  • Nasal congestion
  • Runny nose
  • Abdominal cramping
  • Diarrhea
  • Nausea
  • Vomiting
  • Low blood pressure
  • Blocked airways[1]
  • Loss of consciousness[2]

Top 8 Food Allergy Causes

1. Cow’s Milk

Cow’s milk is the leading cause of food allergies in people of all ages. Some children outgrow milk allergies by the time they turn 2 or 3 years old, though milk allergies end up following many children into adulthood.[3] Cow’s milk is found in many foods, including yogurt, bread, butter, cheese, ice cream, and pastries like donuts, biscuits, and muffins.[4]

2. Eggs

Egg whites and yolks are the most common food allergens after cow’s milk, and mostly affect infants and young children.[5] Eggs are commonly found in foods like mayonnaise, ice cream, pasta, coffee drinks, and most baked goods.

3. Fish

Bass, cod, and flounder are examples of fish that can trigger allergies. Many types of fish contain a protein in their muscles called parvalbumin that contributes to most fish allergies. Enolases, aldolases, and fish gelatin are other known allergens in fish.[6] Unexpected sources of fish include barbecue sauces, Caesar salad dressings, and Worcestershire sauce.

4. Shellfish

Most types of shellfish contain a protein called tropomyosin that has been linked to allergies.[7] Shellfish that can cause allergic reactions are shrimp, crabs, scallops, lobster, oysters, and clams.

5. Peanuts

Peanuts account for the majority of severe food-related allergic reactions around the world and affect children and adults alike.[8] There are at least 7 proteins in peanuts found to trigger severe allergic reactions. Foods that commonly contain peanuts include peanut butter, Thai and Chinese dishes, baked goods, candy, and margarine.[9]

6. Soy

Soybeans and soy products contain up to 16 proteins that have been linked to allergy symptoms in people of all ages, though children are most commonly affected by soy allergies.[10] Soy can be found in foods and products that contain edamame, miso, natto, soy sauce, tempeh, and tofu.[11]

7. Tree Nuts

Almonds, cashews, pecans, pistachios, and walnuts are just some of the tree nuts that cause allergies. Tree nuts contain a number of seed storage proteins and plant defense-related proteins that trigger a range of allergy symptoms, though skin reactions are the most common symptom associated with tree nut allergies.[12]

8. Wheat

Wheat allergies are more common in children than in adults and have been linked to severe reactions such as anaphylaxis. People who are allergic to wheat can experience symptoms when either eating or inhaling wheat. Wheat can be found in many processed foods including bread, pasta, pizza, and beer.[13]

4 Ways to Prevent Food Allergies

1. Avoid Known Allergens

Food allergies can be prevented by avoiding known allergens at all times. Read the labels of all packaged foods and call the manufacturer if you have questions about the ingredients or the facilities in which the foods were prepared. Also, stay mindful of cross-contact when eating at restaurants, cafeterias, home kitchens, and other places where your meal may come into contact with known allergens.[14]

2. Practice Desensitization

Desensitization is the act of eating a small amount of food that causes allergies on a daily basis. This allows the body to develop a tolerance to the food, which may help minimize or eliminate allergic reactions. Desensitization must be done under an allergist’s guidance to reduce the risk for severe reactions and complications like anaphylaxis.[1]

3. Choose Breastfeeding

Breastfeeding is shown to prevent the development of allergic diseases in children.[15] If you are pregnant, consider breastfeeding your child to prevent the development of food allergies. Breastfeeding may not be effective at preventing allergies if you drink cow’s milk, or if you have already started formula-feeding your baby.

4. Inform Friends and Family

Tell your friends, relatives, neighbors, coworkers, and others with whom you interact about your food allergies. This can be helpful when you’re eating at someone else’s house for dinner or when you’re participating in potlucks. Informing community members about your food allergies may help minimize your exposure to known allergens.

Possible Food Allergies Treatment Options

Questions Your Doctor May Ask About Food Allergies Treatment

  • When did you first notice food allergy symptoms?
  • Which symptoms do you experience the most?
  • How long do your symptoms last?
  • Which foods trigger your symptoms?
  • How often do you experience allergy symptoms?
  • How do you find relief from your symptoms?
  • What steps do you take to avoid allergic reactions?
  • Have you ever experienced severe allergic reactions such as anaphylaxis?

Food Allergies May Also be Known as:

  • Food Allergens
  • Food symptoms


  1. Medline Plus. Food allergy.
  2. U.S. Food and Drug Administration. What You Need to Know about Food Allergies.
  3. University of Utah Health. Recognizing and Managing Cow's Milk Allergy in Kids.
  4. Children’s Hospital of Philadelphia. Milk Allergy.
  5. National Library of Medicine. Current understanding of egg allergy.
  6. National Library of Medicine. Fish Allergens at a Glance: Variable Allergenicity of Parvalbumins, the Major Fish Allergens.
  7. National Library of Medicine. Shellfish Allergy.
  8. National Library of Medicine. Peanut allergy: an overview.
  9. University of Rochester Medical Center. Peanut-Free Diet.
  10. National Library of Medicine. Soy protein allergy: incidence and relative severity.
  11. University of Rochester Medical Center. Soy Allergy Diet for Children.
  12. University of Nebraska-Lincoln. Allergenic Foods and their Allergens.
  13. National Library of Medicine. Wheat allergy: diagnosis and management.
  14. Missouri Department of Health and Senior Services. Managing Food Allergies: What You Need to Know.
  15. National Library of Medicine. Role of breast feeding in primary prevention of asthma and allergic diseases in a traditional society.
  16. National Library of Medicine. Current Options for the Treatment of Food Allergy.

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