Prevention of Allergies and Asthma in Children
It has long been known that allergies and asthma tend to run in families, making children where one or both parents have an allergic disease more likely to develop these conditions. Fortunately, there are steps that may delay or possibly prevent allergies or asthma from developing.
Preventing Food Allergies
Food allergies can cause problems ranging from eczema to life-threatening allergic reactions. Common triggers include peanuts, tree nuts, cow's milk, egg, soy, wheat, fish, and shellfish.
Infants with a sibling or at least one biological parent who has allergic conditions are at risk for developing food allergy, especially if they already exhibit allergic symptoms of atopic dermatitis, allergic rhinitis or asthma.
Restricting a mother's diet of specific allergens during pregnancy and while breast-feeding, when a child is otherwise well, is not routinely recommended as a means to prevent food allergies. Most recent information indicates there is no significant allergy prevention benefit to your baby if you avoid highly allergenic foods during this time. Breast milk is the ideal way to nourish your infant. It is least likely to trigger an allergic reaction, it is easy to digest and it strengthens the infant’s immune system. Especially recommended for the first four to six months, it may possibly reduce early eczema, wheezing and cow’s milk allergy. For infants at risk for food allergy where the mother is unable to breast feed, hydrolyzed infant formulas are recommended as hypoallergenic substitutes over cow’s milk and soy formulas.
Between four to six months, single-ingredient infant foods may be introduced, typically including fruits (apples, pears and bananas), vegetables (green vegetables, sweet potatoes, squash and carrots) and cereal grains (rice or oat cereal) one at a time. Food can be introduced this way every 3 to 5 days as appropriate for the infant’s developmental readiness. This slow process gives parents or caregivers a chance to identify and eliminate any food that causes an allergic reaction.
Egg, dairy, peanut, tree nuts, fish and shellfish can be gradually introduced during the same four to six month window after less allergenic foods have been tolerated. In fact, delaying the introduction of these foods may increase your baby’s risk of developing allergies.
An allergist should be consulted if allergic reactions, like moderate to severe eczema, occur or if the infant has a peanut allergic sibling.
Preventing Environmental Allergies and Asthma
Since some airborne substances may trigger allergy or asthma symptoms, reducing contact with these substances early in life may delay or prevent allergy or asthma symptoms. Research for this is clearest with dust mites. If your child is at high risk of developing allergies, there are steps you can take to control dust mites.
Use zippered, "allergen-impermeable" covers on pillows and mattresses and wash bedding in hot water weekly. Indoor humidity should be kept below 50%. If possible, carpets and upholstered furniture should be removed from your infant's bedroom.
Pets and Other Animals
The relationship between early life exposure to animals and the development of allergies and asthma is somewhat confusing and there are many factors to consider. Previous evidence suggested that children exposed to animals early in life are more likely to develop allergies and asthma. More recent research seems to show that early exposure to animals (cats and dogs in particular) may actually protect children from developing these diseases. Newer research also suggests children raised on farms develop fewer allergies and asthma. Talk with your physician to determine what is best for you and your family.
It is very important not to expose your children to tobacco smoke before or after birth. Smoking during pregnancy increases the chance of your child wheezing during infancy. Exposing children to secondhand smoke has also been shown to increase the development of asthma and other chronic respiratory illnesses.
Benefits of Breast-Feeding
Infections that start in the lungs are common triggers of asthma. Since breast-feeding for at least four to six months strengthens a child's immune system, it is helpful in avoiding these infections and, in the long term, asthma.
If you believe your child may have allergies or asthma, it is important to seek the right medical help. An allergist / immunologist, often referred to as an allergist, is a specialist in the diagnosis and treatment of allergies, asthma and other diseases of the immune system. Allergists have completed medical school, at least three years of residency in pediatrics or internal medicine, then at least two years of specialized training in allergy and immunology.
Testing done by an allergist is generally safe and effective for children of all ages. Allergy tests, combined with the knowledge of your allergy specialist to interpret them, can give precise information about what your child is and is not allergic to.
For instance, if your child wheezes when you are at home and you don't know why, you don't have to get rid of your cat if your child's allergy testing shows that he or she is allergic to dust mites but not cats. With this information, you and your allergist can develop a treatment plan to manage or even get rid of your child's symptoms.
When to Proceed with Caution
There are methods of allergy testing that the American Academy of Allergy, Asthma & Immunology (AAAAI) believes are not useful or effective. These include: massive allergy screening tests done in supermarkets or drug stores, applied kinesiology (allergy testing through muscle relaxation), cytotoxicity testing, skin titration (Rinkel method), provocative and neutralization (subcutaneous) testing or sublingual provocation.
• Breast-feeding exclusively for the first four to six months, or using a hypoallergenic formula, may strengthen the immune system while delaying or preventing atopic dermatitis and milk allergy.
• Restricting a mother's diet during pregnancy or while breast-feeding has not been shown to help prevent the development of allergies.
• Solid foods should be introduced gradually between four to six months of age. Egg, dairy, peanut, tree nuts, fish and shellfish can be gradually introduced after less allergenic foods have been tolerated. In fact, delaying the introduction of these foods may increase your baby’s risk of developing allergies.
• Reducing exposure to some allergens, such as dust mites, may delay or prevent allergy or asthma symptoms.
• Exposure to tobacco smoke before and after birth increases your infant's risk of developing wheezing and asthma.
The AAAAI's Find an Allergist / Immunologist service is a trusted resource to help you find a specialist close to home.
This article has been reviewed by Andrew Moore, MD, FAAAAI