Owning a cat appears to have a significant protective effect against asthma for children, according to the results of a study published in the September 2002 issue of the American Journal of Respiratory and Critical Care Medicine.
Researchers studied more than 3000 children 7 and 8 years old living in northern Sweden. Because this area has a cold, dry climate, dust mites and cockroaches are rare, so it is easier to examine the effects of domestic animal allergens only.
Living with a cat lowered the relative risk for asthma by 51% and the incidence of a positive skin test to cat allergens by 38%. The protective effect on the development of asthma was strongest among children with a family history of asthma (relative risk, 0.25%).