When someone is extremely sensitive to dietary substances containing soy, it causes their immune system to overreact and leads to physical symptoms that come out. Some foods that contain the soy protein are soy, soy milk, miso, tempeh, tofu, edamame, soy sauce and soybean butter. If you’re allergic to soy, it means your body has identified some or all of the soy proteins as unsafe substances.
When a person has an allergy, their body begins to produce immunoglobulin E antibodies to the allergen. Being allergic to soy and ingesting it causes these antibodies to signal the immune system to release histamine and a variety of other chemicals. The histamine and other chemicals produce all of the allergic symptoms. The histamine is part of what causes the most responses, such as itchy eyes, rashes, dry throat, nausea, hives, runny nose and diarrhea.
If someone experiences soy allergy symptoms, their throat, lips, face or tongue may swell as well as other parts of the body. They may experience abdominal pain and diarrhea. They can also become nauseous and begin to vomit. Someone with soy allergies might also experience tingling in their mouth, begin to feel itchy, have trouble breathing and see their skin turn red.
It’s rare for someone to have a severe allergic response to soy, but it can happen. This is called anaphylaxis, aka anaphylactic shock, and it usually happens when someone has asthma and the food allergy. With an allergic reaction this severe, a person’s heart might begin to race, and they can be so dizzy and lightheaded that they lose consciousness. It can cause someone’s throat to swell so much that it’s difficult to breathe. Their blood pressure can lower dramatically, and they can even go into shock.
There are factors that put someone at a higher risk of being allergic to soy. Soy allergies are most common in children.
The good news is that with proper diagnosis and a treatment plan like a Food Allergy Action Plan developed by a board-certified soy allergist, soy allergy can be well controlled. Most infants with soy allergy will outgrow the allergy by the time they are 3-5 years old. Getting educated about hidden sources of soy, recognizing allergic reactions and knowing about the medications used to treat the allergy are the keys to living well with soy allergy.
If you have any questions or concerns for expert soy allergists, call the soy allergy experts at Asthma & Allergy Associates and their Food Allergy Center for more information