Little elicits more widespread warm fuzzies and collective contented sighs than the sight of babies and dogs together. To make matters even sweeter, a new study by Finnish researchers has discovered that there are viable health benefits for babies raised around dogs.
The researchers studied almost 400 children from their third trimester through their first year of life, and found that babies raised in homes with dogs have fewer colds and respiratory tract symptoms or infections, fewer ear infections, and require fewer antibiotics during their first year than those raised in pet-free homes. Babies raised amongst cats also showed health benefits, but they were not as pronounced as those babies whose families had dogs.
According to Eija Bergroth, MD, of Finland’s Kuopio University Hospital, “The strongest effect was seen with dog contacts. We do not know why it was stronger than with cat contacts. It might have something to do with dirt brought inside by the dogs, especially since the strongest protective effect was seen with children living in houses where dogs spent a lot of time outside.”
One popular and long-held explanation, the hygiene hypothesis, holds that children’s immune systems develop best when exposed to a small amount of germs. Too many germs overload children’s developing immune systems, while a too-sterile environment is also detrimental because it does nothing to encourage development. Yet Anna Fishbein of the University of Maryland notes that this hypothesis is progressing, saying “It’s become more complicated. It’s no longer just getting exposed to the right number of microbes, but to good bacteria and viruses that alter the microbes in our intestines and protect us against both allergies and infections.”
The evolving hygiene hypothesis is giving way to what Karen DeMuth, assistant professor of pediatrics at Emory University calls “the microbiome hypothesis.” “The microbiome hypothesis,” DeMuth notes, “is that early-life exposure to wide varieties of microbes lets them mix with the microbes in the gut and helps them keep the immune system from reacting against itself and causing autoimmune disease, or from reacting against stuff you should ignore and causing allergy.”
DeMuth is careful to point out, however, that there is no one-size-fits-all approach to germs, microbes, and health, saying “There is also an interaction between these microbes and an individual child’s genetics. Certain people who have a dog in the house are protected against infections and allergies, but some are not.”
Children with allergies or asthma may not fare well with pets in the home. “The absolute wrong thing is to put a dog in the house for kids with asthma,” DeMuth says. “Yes, having a dog in the house early can protect against wheezing or respiratory infections. But this exposure has to happen very early in life.” If expectant parents have allergies or asthma but want to raise their children around pets, Bergroth understands, saying “It is important for the child that its parents can live happily in the home without symptoms.”