Previous studies have shown that children's early exposure to farm animals lowers their risk of developing asthma. Does having a pet dog at home have the same effect? A new study found that children exposed to family dogs at a young age are less likely to develop asthma compared to those who do not have dogs, Medical News Today reported.

"Earlier studies have shown that growing up on a farm reduces a child's risk of asthma to about half," study author Tove Fall, assistant professor in epidemiology at Uppsala University, said in a press release. "We wanted to see if this relationship was true also for children growing up with dogs in their homes."

To determine how early exposure to dogs and other animals affected children's risk of asthma, researchers from Uppsala University and Karolinska Institutet investigated the health registry data of more than one million pre-school age and school age children from nine different sources. They also examined two dog ownership registers.

The researchers found that exposure to pet dogs within the first year of life reduced children's risk of asthma by 13 percent. Their results also confirmed previous studies' results that exposure to farm animals decreases asthma risk; farm animal exposure lowered asthma risk in pre-school age children by 31 percent and in school age children by 52 percent.

"Our results confirmed the farming effect, and we also saw that children who grew up with dogs had about 15 percent less asthma than children without dogs," Fall said. "Because we had access to such a large and detailed data set, we could account for confounding factors such as asthma in parents, area of residence and socioeconomic status."

"For what we believe to be the first time in a nationwide setting, we provide evidence of a reduced risk of childhood asthma in 6-year-old children exposed to dogs and farm animals. This information might be helpful in decision making for families and physicians on the appropriateness and timing of early animal exposure," the authors wrote.

The study was published in the online Nov. 2 issue of the journal JAMA Pediatrics.