Children exposed to dogs and farm animals in infancy enjoy a reduced risk of developing asthma, according to a major Swedish study published last night.
Researchers said that growing up with dogs reduced the risk of developing asthma by about 15% and confirmed earlier reports that life on a farm halved asthma risk.
The findings may reflect the "hygiene hypothesis" of allergy and asthma, suggesting that exposure to common microbes in early life might help tune the immune system.
The study involved some 650,000 children. Some 46,000 pre-school children developed asthma as did more than 11,000 children of school age.
The researchers from Uppsala University, Sweden, reported their findings in the journal JAMA Pediatrics.
They write: "For what we believe to be the first time in a nationwide setting, we provide evidence of a reduced risk of childhood asthma in six-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."
Researcher Professor Catarina Almqvist Malmros said: “These kind of epidemiological studies look for associations in large populations but do not provide answers on whether and how animals could protect children from developing asthma.
"We know that children with established allergy to cats or dogs should avoid them, but our results also indicate that children who grow up with dogs have reduced risks of asthma later in life."
JAMA Pediatr 2 November 2015; doi:10.1001/jamapediatrics.2015.3219
Leave a Reply