Why are we so crazy about our pets? Science.

Owning a pet is good for you physically, psychologically, and socially
Photograph by Ryan Hayslip

To those who don’t have animals, “pet people” can sometimes seem a little crazy. The nicknames, the Facebook photos (heck, the painted portraits), the outfits and accessories, the dog run cliques, the bafflingly detailed stories about “what my cat’s been up to.” And then there’s the cost and inconvenience: the walking, the poop coaxing and scooping, the crate training, the litter box emptying, the middle-of-the-night barking, the endless (endless!) fur, the vet bills, the grooming bills, the cat-sitting and doggy daycare bills.

Like parents of small children, though, pet owners are quick to explain, “If you have one, it’s all worth it.” And scientifically speaking, they’re right. Beyond the subjective—he’s so funny, he’s so sweet, he’s my best friend—there’s plenty of evidence that owning a pet is good for you, physically, psychologically, and socially.

Having a pet lowers your stress level and blood pressure and may be associated with decreased risk for heart disease. Pet owners are less likely to die in the year following a heart attack compared with non-pet owners. And pets keep you active—taking the dog out for regular walks means you’re less likely to be obese. In therapy settings, animals have been shown to calm dementia patients, reduce depression in nursing home residents, and alleviate anxiety among college students.

There’s also a wealth of research showing that social support promotes better physical and mental health. Animals are not only a source of emotional comfort for their owners, they can be a social lubricant; there’s a reason adorable puppies facilitate so many movie meet-cutes. “If you see someone with an animal, you make positive associations about that person. You’re more likely to approach them, engage them in conversation,” says Alan Beck, professor of animal ecology and director of the Center for the Human-Animal Bond at Purdue University. “There’s a reason why presidents have pets.”

Pet owners tend to be less lonely and have better self-esteem than non-owners. “They’re like eternal children; they make us feel needed,” says Sandra Barker, professor of psychiatry and director of the Center for Human-Animal Interaction at Virginia Commonwealth University School of Medicine. Beck adds, “It’s assumed that lavishing time and attention on your pet means it’s taking away from human relationships. But we see the opposite. Being a pet owner is not a substitute for positive human interaction, it’s actually a facilitator.” Pets can even help those who have trouble with sociability: One study found that autistic children are more likely to talk to other kids, smile, and laugh when they’re around animals.

Part of our attraction to pets is innate. “Research has shown that we’re wired to respond to cute, infant-like behavior and looks,” Beck says. “And we’ve selected domesticated animals for those ‘youth’ traits. An adult dog is basically a puppy wolf.” Still, the allure goes beyond the visual appeal—we’re also emotionally Velcroed to our furry friends. Back in 1988, Barker measured how close subjects were to their dogs versus their human family members. “We found that there was no significant difference between people and their closest dog and their closest family member,” she says. In other words, we really can love our pets just as much as our spouses, our siblings, and even our children.

But do they love us back? To answer that question, for the past four years, Gregory Berns, a neuroscientist and professor of psychology at Emory University, has been performing functional MRI scans of dogs to study how their brains work. “Up until then, most academic research on what goes on inside an animal’s head was largely restricted to lab animals, like rats or chimps,” Berns says. “But dogs are special. In many ways, they’re more like us than chimps because they live with us, and their evolution has changed as a result of their relationship with us over thousands of years.”

Berns wanted to know: Are dogs just hanging around and pretending to be social in order to tap our weak spots in exchange for food and shelter? Or is the bond based on more than that? In the study, he has looked at how the reward systems in a dog’s brain respond to owners, strangers, and computers. “If it was really just about the food, then it wouldn’t matter who they’re interacting with,” says Berns, who in 2013 wrote a book about his project called How Dogs Love Us. “But we’ve shown it does make a difference. For many dogs, food is just incidental. Praise from their owner is an even more powerful reward, and we see it in their brains.”