Counterintuitive, at first, but it makes perfect sense. “The old thinking was that if your family had a pet, the children were more likely to become allergic to the pet. And if you came from an allergy-prone family, pets should be avoided,” says researcher James E. Gern, MD, a pediatrician at the University of Wisconsin-Madison, in the Journal of Allergy and Clinical Immunology. But a number of new studies suggest that kids growing up in a home with “furred animals”–which can include cats and dogs, as well as farm animals–will have less risk of allergies and asthma.
In his recent study, Gern analyzed the blood of babies immediately after birth and one year later. He was looking for evidence of an allergic reaction, immunity changes, and for reactions to bacteria in the environment. If a dog lived in the home, infants were less likely to show evidence of pet allergies. They also were less likely to have eczema; and they had higher levels of some immune system chemicals–a sign of stronger immune system activation. This sounds similar to the concepts explored in the hygiene hypothesis.