Can Puppies Prevent Childhood Obesity?

Walking a dog is one relatively painless way of getting exercise and burning calories. One estimate is that a 150 pound person can burn 204 calories in an hour of dog walking, more if you’re going uphill, the dog pulls you, or makes you walk faster. But there may be a less well established benefit of dog ownership for babies who are years away from being able to walk their pets.

In recent years scientists have been researching the effects of the microbes that we have in our guts (see my Psychology Today blog post “Are the bugs in your gut making you gain weight?”). Humans have more than one hundred trillion of these tiny bugs in the gut and they play a significant role in digestion and weight gain. There is evidence that some of these microbes can contribute to obesity while others may decrease weight gain. Researchers have been studying microbes with the hope that it might be possible to fight obesity by increasing the good microbes that may make obesity less likely. Perhaps infants could be “inoculated” against obesity by early exposure to helpful microbes. New research suggests that puppies could be one means of transmitting these helpful microbes to newborns.

Researchers at the University of Alberta in Canada found that furry pets might expose babies to two types of bacteria that then get established in the babies gut. These bacteria, ruminococcus and oscillospira, have been linked to lower odds of allergies and obesity. The researchers analyzed poop samples from 746 babies and found that when there were dogs or cats in the home during pregnancy and early infancy babies were twice as likely to have high levels of these two types of gut bacteria. Although the study doesn’t prove that dogs or cats are responsible for the helpful changes in gut microbes, it’s likely that pets can transfer the beneficial microbes when the baby is near the animal or get the pet microbes that are present in furniture, floors, or household dust.

While no one is suggesting that parents put a puppy in their baby’s crib, being around a furry critter might be protective against future development of obesity and allergies.