Most processed foods contain either soy or dairy, or both. Often these ingredients go by names that do not immediately alert you to the fact that they are soy or dairy products, such as MSG, protein extender or casein. If you are allergic to corn or soy, your best bet is to prepare as many of your own meals as possible from fresh, unprocessed ingredients. This approach gives you the advantage of knowing firsthand exactly what goes into your food.
Fresh Fruits and Vegetables
Fresh vegetables contain no soy or dairy, with the sole exception of edamame, or the pods of the soybean plant. If you avoid edamame and choose from the other available fruits and vegetables, you will find that you have a wealth of foods to choose from that do not contain soy or dairy. Prepare fresh vegetable salads with a simple dressing of olive oil and vinegar, or lightly steam vegetables until they are just tender. Stew fruit in a small amount of fruit juice that contains no additives or preservatives, adding only a little bit of sweetener, then thicken it by sprinkling in a little bit of rice flour to create a simply, tasty compote.
Free range meat, poultry and fish contain no soy or dairy ingredients. Although many factory feedlots feed soy to beef, cows and chickens, there is no evidence that eating an animal that has eaten soy will trigger a human soy allergy. However, if this is a concern to you, buy your meat at your local farmer's market where you can speak directly to the producer and make sure that the animal whose meat you are buying has not eaten soy. Avoid seasoning your meat with soy sauce or worcestershire sauce, which both contain soy.
Whole and refined grains contain no dairy or soy because they are simple foods made up of a single ingredient. White or brown rice, barley, wheat berries, quinoa and polenta are all examples of grains that you can eat without trouble if you are avoiding dairy or soy, especially if you prepare them yourself. Cook white or brown rice, barley, wheat berries or quinoa covered, in water measuring twice the volume of the dry grain, until they absorb all of the water. Cook polenta in three parts water to one part polenta. Add a bit of olive oil and salt to the water, then bring it to a boil and drizzle in the polenta, stirring constantly until it thickens. Many cooks add cheese to their polenta, but you can make a tasty, dairy-free version yourself, with a minimum of effort.