Mary, a 28-year old school teacher with a long-term history of hay fever and atopic dermatitis is currently eight months pregnant.  Her husband has also suffered from asthma since childhood.  These parents are wondering if there is any way to delay or even prevent their future newborn baby from developing allergies.

People with atopy have the tendency to develop closely linked allergic disorders– atopic dermatitis, hay fever and asthma.  Patients with atopy have a genetic predisposition to producing specific IgE antibodies to allergens.  These antibodies trigger inflammation leading to different allergic symptoms.  Atopy frequently runs within families.  Therefore, infants or children with a family history of asthma, eczema or hay fever have a higher risk of developing allergic disorders.

In general, newborn infants are more likely to become allergic to foods than older infants.  The approach for preventing or delaying a food allergy is to postpone exposure to potential food allergens during the early months.  Mothers should breastfeed their infants for at least six months if possible, since breast milk is much less likely to produce an allergic reaction and can strengthen the child’s immune system, thereby decreasing respiratory infections.  Infants who are not breast-fed should be offered pre-digested, protein hydrolysate formulas, rather than cow milk or soy-based formulas.  Infants should not be fed solid foods until they are six months old.  When infants are six to twelve months old, vegetables, rice, meat, and fruit can be introduced into their diets.  After the child is one year old, milk, wheat, corn, citrus and soy may be added. At two years of age, the child may have egg introduced into the diet. Finally, at age three, fish and peanuts may be included.

However, several observational studies have recently suggested that early introduction of potentially allergic food may be associated with a decreased risk of developing food allergy.  The new guidelines from NIAID in January, 2017, recommended that the highest risk infants, those with severe eczema and egg allergy, should be introduced to age-appropriate peanut as early as four to six months of age to reduce the risk of peanut allergy.  The new guidelines are quite different from the old ones.

Similar to managing food allergies, reducing contact at an early age with inhalant allergens, particularly dust mites and animal dander, may delay the onset of hay fever or asthma symptoms.  The steps to reducing dust mite and animal dander include using zippered plastic covers on pillows and mattresses, and washing bedding in hot water every seven to ten days.  Indoor relative humidity should be kept below 50% and, optimally, carpets, upholstered furniture, or objects should be removed from the infant’s bedroom.  Also, it is best to avoid placing very young children in group day care to decrease their exposure to respiratory infections, and consequently, triggering asthma. Maternal smoking during pregnancy is associated with increased wheezing during infancy.  Exposing children to secondhand smoke in the home can also trigger asthma.  Therefore, it is extremely important that infants are not exposed to tobacco smoke before or after they are born. Allergic disorders cannot be cured or prevented entirely, but by delaying exposure to allergens, we may be able to postpone the development of allergic disorders in children.