Childhood Allergies Can Be Solved, Though That's Not Always Easy to Do

April 4, 2006 — -- If parents feel a bit confused about how to keep their children safe from allergies and asthma, it's no wonder: Even the experts disagree on the subject.

Are allergies inherited from parents, as some researchers claim? Or is it a child's environment that causes the sneezing, coughing, wheezing and other misery that allergies and asthma bring?

Some parents wonder whether they should expose their kids to potential allergens at an early age to ward off allergies and asthma. Or is it a better idea to keep a child away from pets, pollen, smoke, and foods like nuts and fish?

Though doctors continue to debate these issues, the latest research offers clear, common-sense advice for avoiding or minimizing childhood allergies.

A growing body of research supports the "hygiene hypothesis," which is the theory that early childhood exposure to animals, plants and other allergens will prevent or minimize allergies and asthma. So, an overly hygienic environment, like an immaculate home and a minimum of outdoor activity, may lead to more allergies, proponents claim.

"The idea is that a child's immune system shortly after birth needs a little help to get it started in the right direction," said Harold Nelson, an allergist and professor of medicine at the National Jewish Medical and Research Center in Denver.

"It is the dominant hypothesis at this time, and there's a huge amount of data that supports this," Nelson added.

Nelson cited recent research that found a 50-fold increase in the incidence of allergies and asthma among children growing up in more affluent urban areas over children living in native villages in Africa.

Other research from Europe finds children living in rural and farming communities who grow up surrounded by animals, plants, and other potential allergens have fewer allergies than city-dwelling kids.

But does this mean genetics and a family history of allergies count for nothing?

"Genetics are huge," Nelson said. "But given the choice between the two, the environmental influence is greater than the genetic in epidemiological studies."