Food allergies among children are more common today than they were 10 years ago, says Dr. Wendy Sue Swanson, a Seattle-based pediatrician and mom to two young boys.

Swanson cites a report in Pediatrics, the official journal of the American Academy of Pediatrics, but why food allergies are more common remains under debate. Some theories suggest it's due to increases in clinical diseases, while others attribute it to greater awareness by physicians and other health care providers, as well as parents.

The most common food allergies are milk, eggs, nuts, soy, wheat and shellfish.

Families with known food allergies should be careful when it comes to the introduction of those particular foods.

Swanson recommends parents be on the alert if a child's brother or sister has a food allergy.

"Siblings are the most like you than anyone on the planet," Swanson tells ParentDish in a phone interview.

If Mom is the one with the food allergy, she might want to not only avoid the trigger foods when breast-feeding, but also during pregnancy.

Children can outgrow allergies over time. Since kids' immune systems are always changing, parents can continue to try certain foods over the years, as there's a possibility that their bodies can outgrow the allergy.

As a general rule, Swanson recommends restricting nuts or nut particles, egg whites and all fish until age 1.

"White fish and shellfish tend to be more allergy provoking," she tells ParentDish. "If there's a strong family history of a shellfish allergy, wait until the child is 2 years old before introducing."

Statistics say 30 to 50 percent of kids who are sensitive to cow's milk are also allergic to soy. Swanson recommends non-cow's milk or non-dairy formula, of which there are two commercially available: Alimentum and Nutramagen.

Wheat is among the top five most common food allergies. If there's a wheat allergy in your family, be mindful of the teething biscuits you give your child. Try brands with barley or rice first.

The appearance of eczema, the itchy red patches on your baby's skin, as well as stringy stools or excessive spit or vomit in infants ages 2 months to 6 months, can be signs of a food allergy.

The baby's sensitivity "could be from the cow's milk or soy protein in standard and soy formula, but if a baby is breast-feeding, it could be from a constituent in Mom's diet," Swanson says. "We often start with dairy elimination with moms who are breast-feeding, but sometimes have to exclude even more, especially if testing confirms sensitivities or allergies in baby."

Antihistamines can work well for eczema, but Swanson advises parents to never self-treat for food allergies. Talk to a pediatrician or family doctor first.

If a child's lips swell or get red immediately after feeding, or he or she breaks out in hives on the face, immediately stop feeding that food until talking with a physician, Swanson says. Splotchy skin is considered mild, but if your child starts to wheeze, cough or experience vast swelling, that's considered an emergency.

As far as prevention goes, Swanson recommends waiting until your child is 6 months old to introduce solid food, at no more than two new foods per week. Wait a few days before introducing something new, as you need a good trial of each new food. And don't halt this trial period once your child turns 1. You need to do this with every new food, she says.

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