By Elizabeth Smoots, M.D.
Allergy Alert: The Hazards of Healthy Childhood Foods
Daniel was breast-fed as an infant, so his mother didn't realize he was allergic to cow's milk until she tried to wean him. She noticed that he vomited for hours after taking a bottle and broke out in red welts if its contents got on his skin. Goat's milk caused a similar reaction. Ultimately, she was forced to abandon these foods in favor of medically recommended substitutes.
Daniel's situation is not unusual. Food allergies affect up to 2 million -- or 8 percent -- of children in this country. Milk allergy ranks among the top eight food allergies; the others are eggs, peanuts, tree nuts, soy, wheat, fish, and shellfish.
Living with a food allergy
For a person with a true food allergy, the only treatment that really works is the complete avoidance of that food -- a potentially difficult task. Allergy shots are ineffective, and medications or adrenaline injections are primarily used for life-threatening reactions (anaphylaxis).
With food avoidance, children often outgrow their allergies after several years. However, sensitivity to highly allergenic foods -- especially those likely to cause anaphylactic reactions, such as peanuts, tree nuts, fish, and shellfish -- usually persists for life.
Risk factors for food allergies
Today, Daniel is an adult and expecting a child of his own. He and his wife wonder how to prevent their first child from developing food allergies. Their concern is legitimate; a family history of food allergy is a key risk factor for the disorder. Other factors that may increase a child's risk include the following:
Family history of eczema, asthma, hay fever, or other allergies
Birth in the spring or fall
Premature birth or low birth weight
Passive exposure to cigarette smoke or pollution before or after birth
Exposure to viral infections early in life
Preventing food allergies
An infant may become sensitized to food allergies before birth through the placenta, or after birth from exposure to breast milk, formula, solid food, or airborne particles. The majority of studies have found that avoiding allergenic foods during pregnancy is not preventive. For parents prone to allergies, however, studies suggest several ways to help prevent your child from developing food allergy symptoms during the first two years of life.*
Breast-feed your child for at least six months. Studies do not support dietary restrictions for nursing mothers, except when the child has a severe food allergy (anaphylaxis) or, perhaps, chronic eczema.
Supplement or wean with a hypoallergenic formula that is extensively hydrolyzed (pre-digested), like Nutramigen, Progestimil, or Alimentum. Partially hydrolyzed formulas, like Good Start, are more allergenic.
Delay starting solid foods until 6 months of age.
Wait until after your child's first birthday to introduce cow's milk, corn, wheat, soy, and citrus.
Wait until your child is 2 years old to introduce highly allergenic foods, such as eggs, tree nuts, peanuts, and seafood.
Don't smoke while pregnant or after your child is born.
Protect your child from exposure to infections, and consider delaying daycare.
*There is considerable debate among experts about the safety and effectiveness of some these preventive practices. Always consult with your health care provider before making dietary changes, especially if you have a family history of severe food allergy (anaphylaxis).
Rx.magazine feature story: Food Allergies: Rare but Dangerous
Outside link: The Food Allergy Network
Outside link: American Academy of Allergy, Asthma, and Immunology