Study Reveals Dogs May Lower Childhood Asthma Risk

Research conducted by the Hospital for Sick Children in Toronto has revealed that children who grow up with dogs may significantly reduce their risk of developing asthma compared to those raised with cats. The study, presented on September 25, 2025, at the European Respiratory Society Congress in Amsterdam, found that babies exposed to dog allergens were less likely to experience asthma symptoms.

The analysis involved tracking the health of 1,050 infants from three to five years old. While 6.6 percent of the children were diagnosed with asthma, those exposed to higher levels of the dog allergen Can f1, which is found in dog skin and saliva, exhibited a 48 percent lower risk of developing the condition. The study also noted that these children demonstrated better lung function, measured by their ability to exhale air forcefully after taking a deep breath.

Dr. Jacob McCoy, the lead author of the study, explained that while cat allergens showed no significant association with asthma risk, the findings on dog allergens suggest a potential protective effect. “We found that exposure to dog allergens was linked to improved lung function and a reduced risk of asthma,” he stated. The researchers speculated that early exposure to canine allergens might alter the nasal microbiome or affect immune system responses, although further research is necessary to clarify these mechanisms.

Asthma is a prevalent chronic respiratory condition among children, particularly in the first four years of life. It arises from complex interactions involving genetic predispositions and environmental factors, including allergies and air pollution. Dr. McCoy emphasized the importance of understanding indoor allergens, as children spend significant time in their homes.

In light of these findings, experts have begun reassessing previous recommendations regarding pet ownership in households with children at risk for asthma. Dr. Erol Gaillard, chair of the European Respiratory Society’s expert group on pediatric asthma and allergy, remarked, “This is potentially good news for families with pet dogs; however, we need to know more about this link and how living with pets affects children’s developing lungs in the longer term.”

Sarah Sleet, chief executive at Asthma and Lung UK, expressed the need for more extensive research to understand the implications of dog ownership on childhood asthma. “Previously, advice often suggested removing pets from homes of children who wheeze or are at risk of developing allergic asthma. This new research suggesting a dog in the home could actually reduce the risk of developing asthma is fascinating,” she said.

The study highlights an ongoing challenge in respiratory research, underscoring the need for increased investment to better understand asthma’s causes and potential preventive measures. “Decades-long underinvestment has left lung research on life support. Urgent action is needed to increase investment into lung research to give everyone fighting for breath a future,” Sleet added.

In related news at the congress, researchers showcased new technology aimed at enhancing early lung cancer diagnosis. A robot-assisted bronchoscope demonstrated remarkable efficacy, allowing doctors to reach and biopsy more than 84 percent of small tumors that traditional methods could only access in 23 percent of cases. This innovative tool, which costs approximately €1 million, represents a significant advancement in the fight against lung cancer, enabling earlier intervention when treatment is more effective.

As the understanding of the interactions between pets and childhood health evolves, this study opens new avenues for research that could lead to better health outcomes for children around the world.