An April 2017 Canadian study published in the journal Microbiome has found that babies from pet-owning families (70 percent of which had dogs) possessed more microbes linked with lower allergy and obesity risk than their pet-less counterparts, setting them up for a healthier future.
The team, from the University of Alberta, studied fecal samples from the Canadian Healthy Infant Longitudinal Development study, which is made up of 20 years' worth of research. It was discovered that babies in the womb and early after birth (up to three months) who had been exposed to pets had higher levels of the Ruminococcus and Oscillospria bacteria — both of which have been linked to reduced levels of childhood allergies and obesity.
Scientists have theorized that exposure to dirt in early life — for example, in a dog's fur and on its paws — creates early immunity in newborn children. However, it seems that there is only a certain amount of time in which the effects of these microbes can be felt.
"There's definitely a critical window of time when gut immunity and microbes co-develop, and when disruptions to the process result in changes to gut immunity," said Anita Kozyrskyj, PhD, who led the research. "It's not far-fetched that the pharmaceutical industry will try to create a supplement of these microbiomes, much like was done with probiotics."
Pet exposure was shown to affect the gut microbiome indirectly — from dog to mother to unborn baby — so, even if the dog was no longer present in the household after birth, this healthy bacteria exchange might still take place. Furthermore, it was found that three birth scenarios known to reduce immunity in newborns (C-section versus vaginal delivery, antibiotics during birth, and a lack of breastfeeding) did not have an effect on microbe levels.