Soy (also called soya, soy bean, or glycine max), is among the most common foods that cause allergic reactions. Researchers are still not completely certain which component of soy causes the reactions, but so far 15 allergenic proteins have been found in soy.
Soy milk, soy flour, soy grits, soy meal, soy sauce, soy oil and more! Soy has become one of the most frequent and common food additives in the modern diet, so avoiding soy can be very difficult for families. Not all soy products cause reactions. Some fermented soy foods are less allergenic than raw beans. Soybean oil (which does not contain protein) may not cause symptoms. It all depends on you and your personal allergies.
The most commonly reported symptoms seen with this kind of allergy include: atopic dermatitis (eczema), urticaria (hives), asthma, allergic rhinitis, anaphylactic shock and digestive symptoms. Other conditions including acne, canker sores and colitis are not uncommon.
It is not unusual for people who are allergic to soy to cross react to other foods, such as peanuts, wheat, certain beans (or legumes) and other foods. But don’t be caught unaware: many foods that you already have in your kitchen contain some type of soy food, even if the word “soy” isn’t on the label. Here are other terms that may also imply soy ingredients:
- Glycine max
- Hydrolyzed vegetable protein (HVP)
- Monosodium glutamate (MSG)
- Vegetable oil
- Vitamin E contains soy bean oil
If you are allergic to soy, read all ingredient labels, and if in doubt, call the manufacturer of the product before buying it.
As with most allergies, avoidance is key. Make sure to read all labels for foods, medicines, cosmetics, creams and ointments that may contain any type or amount of soy. A history of allergic reactions shortly after exposure to soy might suggest an allergy. However, this should be confirmed with a skin prick test or RAST. Talk to your doctor about a complete diagnosis.
SOURCE: This information should not substitute for seeking responsible, professional medical care. First created 1995; fully updated 1998; most recently updated 2005.
© Asthma and Allergy Foundation of America (AAFA) Editorial Board