Children with food allergies have to be made aware of their condition so that they know what they can and can't eat -- especially if they're at risk for anaphylaxis. Their teachers and other caregivers should also be informed. For most children with food allergies, nutrition isn't too much of an issue, since there are plenty of foods that they're not allergic to. The most common food allergies are to shellfish, dairy, eggs, peanuts, tree nuts, soy, wheat and fish. Assuming that your child is only allergic to one of these categories, there are ways to get around allergenic foods.
For children with dairy allergies, soy, rice and almond milk are usually good substitutes. There are even ready-made nondairy versions of yogurt, margarine, cheese and chocolate. Products that contain dairy are normally marked as such, which makes avoidance easier. Likewise, foods with wheat in them are normally marked. To replace wheat flour in a child's diet, other grains are normally ok: Oats, rice, rye, barley and corn are all made into flours. Soy allergies may put a child at risk for allergies to other members of the legume family, too, so it's important to know exactly what risks pose a problem for your child.
The most important trick when it comes to children with food allergies is to be cautious and aware. You need to know all the alternate names that indicate allergenic ingredients (for example, gluten indicates wheat) and you need to remember to read labels. The other trick is to avoid cross-contamination. In many cases, the allergens from one food can get into a food that's not normally an allergy problem because they were prepared in the same kitchen or using the same utensils. With a little vigilance, children with food allergies should have no problem eating a balanced diet.