This information is approved and/or reviewed by U-M Health System providers but it is not a tool for self-diagnosis or a substitute for medical treatment. You should speak to your physician or make an appointment to be seen if you have questions or concerns about this information or your medical condition. Exención de responsabilidad en Español | Complete disclaimer
A soy allergy is a reaction by your child's immune system to the protein in soybeans. Our immune systems normally respond to bacteria or viruses that attack the body. A food allergy occurs when the body's immune system mistakenly believes that a harmless substance (such as proteins found in soy) is harmful. In order to protect the body, the immune system creates substances called antibodies to that food. The next time you eat that particular food, your immune system releases huge amounts of chemicals, such as histamines, to protect the body. This is what causes the warning symptoms.
Soy is one of the 8 foods that are responsible for most food allergies in children. The other foods include eggs, cow's milk, peanuts, tree nuts (such as walnuts and cashews), wheat, fish, and shellfish.
Soybeans are in the legume family (kidney beans, lentils, peas, and peanuts). Some people are allergic to more than one type of legume. A soy allergy is most common in infants and is usually noticed by 3 months of age. Most children outgrow this allergy by 2 or 3 years of age.
If you think your child is allergic to soybeans, soy products or any other food, it is important to get a diagnosis from your healthcare provider or allergist. You should look for the following symptoms, which can range from mild to severe:
Although rare, it is possible to have an allergic reaction called anaphylactic shock. This is a serious reaction that is sudden, severe, and can involve the whole body. It can cause swelling of the mouth and throat, dangerously lower blood pressure, and trouble breathing. This type of reaction is a medical emergency. It is treated with epinephrine (a medicine that is given by injection). Usually parents or caregivers of children who have severe allergic reactions carry their own shot kits, just in case of emergency.
An allergic reaction to a food usually starts within minutes but may be delayed 2 to 4 hours. It usually lasts less than 1 day. The more severe the allergy, the smaller the amount of food it takes to cause a reaction.
If your child is only allergic to soy, you can use regular (non-soy) baby formula. However, about half of the children with a slow-onset milk allergy are also allergic to soy. In these cases, you will need to switch to a hypoallergenic formula. There are two types of hypoallergenic formulas.
The only treatment for a child with a soy allergy is to completely avoid soy and foods that contain soy products. Many foods contain soy, such as baked goods, cereals, sauces, soups and even canned tuna. You will need to change the way you shop and prepare foods. Eliminating all the products in which soy products are found may lead to vitamin deficiency. It is a good idea to have a pediatric dietitian check your child's diet from time to time.
The first step is to learn to read labels and become familiar with ingredients that contain soy or soy products are present. Avoiding soy can be difficult as soybeans are used in most processed foods found in this country. Ask about the ingredients in foods prepared in restaurants when you eat out.
Foods and ingredients that contain soy
Foods that often contain soy (check label or ask)
Reading labels to avoid allergens has become a lot easier. Foods that contain milk, eggs, fish, shellfish, peanuts, tree nuts, wheat, or soy products must list the food in plain language on the ingredient list. For example, tempeh (soy). These possible allergens must be listed even if they are part of a flavoring, coloring, or spice blend. There are still some things to watch out for when reading food labels:
It is very important for you to know less common names and scientific names for food ingredients.
Research shows that most people with a soy allergy may safely eat soy lecithin and refined soybean oil. Ask your healthcare provider if it is OK for your child to have these foods.
Your child can still have a nutritionally complete diet as well as continue to enjoy some kid favorites. The primary nutrients found in soy are protein, calcium, fiber, B vitamins and iron. It is not difficult to provide your child with a nutritious diet, using healthy unprocessed foods from all the food groups. You may need to prepare desserts, such as cookies and cakes from scratch or buy specialty products from the health food section of your grocery store or health food store. There are also Web sites where you can buy specialty foods online (such as http://www.allergygrocer.com). To be on the safe side, buy products that have an 800 number for you to call and ask about ingredients.
It is also helpful to get cookbooks for people with food allergies, such as The NEW-Food Allergy and Anaphylaxis Network (FAAN) Cookbook - Cooking Allergy-Free Everyday. Visit the Web site at http://foodallergy.org or call 800-929-4040 to order this cookbook and others.
