A soy allergy is when your body reacts to soy protein. Soy protein is a product of soybeans and it’s in many foods. If you are allergic to soy, your immune system will react anytime you come in contact with it. Symptoms usually happen within minutes or hours. They may include: If you have more serious allergy symptoms, you may have a severe reaction called anaphylaxis. It needs immediate care. Signs of anaphylaxis include: If you or someone you know has signs of anaphylaxis, call 911. It’s a medical emergency. Allergies happen when your immune system overreacts to something. If you have a soy allergy, soy proteins
trigger your immune system to react. This will happen anytime your immune system is exposed to this protein. Part of this reaction is a release of chemicals including histamines. These chemicals cause your symptoms. Some things make soy allergy more likely. They include: If you think you have a soy allergy, your doctor can test for it. They may recommend these tests: If you have a soy allergy, you need to do more than skip soy sauce and tofu. Soybeans are a big part of processed foods, too. Do these things to protect yourself or your child from an allergic reaction:What Is a Soy Allergy?
Soy Allergy Symptoms
Soy Allergy Causes and Risk Factors
Soy Allergy Diagnosis
Soy Allergy Prevention
Soy foods to stay away from
If you have a soy allergy, do not eat these foods:
- Edamame
- Miso
- Natto
- Soy sauce and shoyu sauce
- Soy-based fiber, flour, grits, nuts, or sprouts
- Soy-based milk, yogurt, ice cream, or cheese
- Soy protein
- Tamari
- Tempeh
- Teriyaki sauce
- Textured vegetable protein (TVP)
- Tofu
Foods that may contain soy
These foods may have soy:
- Baked goods (breads, cookies, and crackers)
- Canned broth and soup
- Canned tuna and meat
- Cereals
- Frozen dinners
- High-protein energy bars and snacks
- Ice cream
- Infant formula, baby foods, and cereals
- Low-fat peanut butter
- Meat substitutes
- Processed meats, like deli meats
- Salad dressings, mayonnaise, gravy, and sauces
- Vegetable oil
- Worcestershire sauce
Other names that may mean soy ingredients
You may want to skip any products with these names on their ingredient lists.
- Glycine max
- Hydrolyzed vegetable protein (HVP)
- Mono-diglyceride
- Monosodium glutamate (MSG)
If you see an ingredient you aren’t familiar with, follow a simple rule: When in doubt, look it up. You can email the maker of the product if you're still not sure about something.
What Is Soy Allergy?
Soy allergy is more common in infants and young children than in older children and approximately 0.4% of infants in the U.S. have soy allergy.1 Most children eventually outgrow their allergy to soy, although some individuals remain allergic to soy throughout their lives.
When a person with a soy allergy is exposed to soy, proteins in the soy bind to specific IgE antibodies made by the person’s immune system. This triggers the person’s immune defenses, leading to reaction symptoms that can be mild or very severe.
Soybeans are a member of the legume family. Beans, peas, lentils and peanuts are also legumes. While it is rare for peanut allergic patients to react to soy, the reverse is not true. One study found that up to 88% of soy-allergic patients had peanut allergy or were significantly sensitized to peanut. Individuals with soy allergy were more likely to be allergic or sensitized to major allergens including peanuts, tree nuts, egg, milk and sesame than to non-peanut legumes such as beans, peas and lentils.1
About 0.4 percent of children are allergic to soy.
1Savage JH, Kaeding AJ, Matsui EC, Wood RA. The natural history of soy allergy. J Allergy Clin Immunol, 2010;125:683-86.