In a six-year study of 9,000 children, it was discovered that growing up with a dog leads to a low level of sensitization to allergens.  This was also true of children who did not have a dog in the home, but had frequent contact with dogs.  The children were not only less sensitive to animal dander, but also pollen.

While many studies regarding exposure and allergies are retrospective studies, this study first asked parents to fill out a questionnaire about their child’s allergy symptoms, and some children had blood drawn to check for antibodies to allergens. 

I have long suspected that the wave of antibacterial this and antibacterial that has lead to us being more sensitive to allergens than ever before. 

However, in many cases, it is not feasible to keep a cat or dog around the house due to asthma and allergies.  My asthma is now controlled through Singulair and Advair, so I can have 2 dogs at home.  It now takes about a couple hours before I start to have a reaction to cats.  Before medication, if I was around a cat, I would have problems breathing in about 20 minutes, and with dogs, it would take about 45 minutes.