Allergies to both dairy and soy are most common in infants and small children, with most allergic patients outgrowing the allergies by age five. According to the Food Allergy & Anaphylaxis Network, 2.5 percent of children younger than three years of age are allergic to milk, and many of these children develop a soy allergy as well. Currently, the only treatment for these food allergies is avoidance and reversal of any reactions that occur.
Background
Allergy to milk or soy protein occurs when your body mistakenly identifies the protein as foreign and forms IgE, or immunoglobulin E, antibodies against it. These antibodies recognize the food proteins the next time you ingest them and start a cascade of events that results in the symptoms of an allergic reaction. You can be tested for IgE to food proteins, so if your physician is concerned about an allergy to milk or soy he may do a blood test looking for IgE against milk or soy. A skin test can also be performed for diagnosis in which the surface of your skin is scratched with a small amount of the allergen and the resultant reaction is then measured.
Symptoms
Symptoms of an allergy to dairy or soy begin minutes to an hour after ingestion of the culprit food. Symptoms may be mild and include itching, mild rash, rare hives or worsened eczema. If you are severely allergic, you may develop symptoms of lip swelling or tingling, difficulty breathing, coughing, wheezing, abdominal pain, nausea, vomiting, dizziness or a combination of these symptoms. An allergic reaction can be life-threatening and occur quickly, so prompt treatment to reverse a reaction is extremely important if you accidentally ingest the food to which you are allergic.
Avoidance
If you are allergic to soy, you should avoid soy in all forms including soy flour, soy fiber and soy albumin. Soy can be found in soy milk, soybean, soy sauce, tofu, edamame, miso, natto, tempeh and tamari. If you are allergic to milk, you must avoid all milk and dairy products including cheese, yogurt and foods that contain casein and whey. Fortunately, both milk and soy are required to be listed on food labels by the Food and Drug Administration. If your infant is allergic to both dairy and soy, you may need to use an elemental formula. This is a formula that is broken down so extensively that the immune system cannot recognize soy or milk protein.
Considerations
Despite your best efforts, you may encounter soy and milk protein in your diet. Your physician will provide you with a food action plan so that if you accidentally ingest the food to which you are allergic, you have a plan in place to treat the reaction. For a mild reaction that involves a slight rash, your physician may suggest that you take an antihistamine such as benadryl. If you have a severe reaction that involves difficulty breathing, vomiting or dizziness, your physician will have you use injectable epinephrine to reverse the reaction. This medication, called an epi-pen, should be carried with you at all times in case of an accidental exposure to dairy or soy.
