A growing body of research suggests that having a pet can help make people healthier. For example, in a 2017 study in Scientific Reports that followed more than 3 million Swedes for over a decade, dog owners were less likely to die from cardiovascular disease (or any other cause) than non-dog owners.
And a 2019 study in Mayo Clinic Proceedings, which involved more than 1,700 people in the Czech Republic, found that pet owners—of dogs, in particular—had higher cardiovascular health scores than their petless counterparts, indicating increased levels of physical activity and better diet and blood sugar profiles.
Granted, these studies were observational and established only a link, not cause and effect. Perhaps pet owners are healthier to begin with (which enables them to take care of a pet in the first place), or perhaps pet ownership is simply a marker of a healthier lifestyle. But it may also be that having a dog, especially, requires owners to engage in physical activity that they might not do otherwise, since they have to walk their canine charges—and that alone could improve their health.
But there’s more to it. Scientists are also confirming what many pet owners like myself know intuitively: Having a pet can help reduce stress by providing an especially comforting form of social support. And reduced stress affects physiological processes in the body that lower the risk of disease beyond the effects of physical activity.
Consider a 2001 study in Hypertension, in which 48 people with high blood pressure were given either the blood pressure drug lisinopril or lisinopril plus a pet (cat or dog) for six months. The drug significantly reduced blood pressure in both groups. But when stressed with mental arithmetic and speech tasks, those who had received pets exhibited lower heart rate (81 versus 91 beats per minute, on average) and lower blood pressure (131 vs. 141 systolic; 92 vs. 100 diastolic).
More recent research has shed light on the ability of pets to reduce stress at the hormonal level. Reporting in AERA Open in 2019, investigators at Washington State University randomly divided 249 undergraduate students into four groups: hands-on petting of cats and dogs for 10 minutes; watching other students pet the animals for the same amount of time; simply viewing a slideshow of the animals; or no touching or viewing of the animals at all. The upshot: Levels of the stress hormone cortisol, as measured in saliva, were found to be significantly lower in the hands-on petters after the session than in the three other groups. Elevated cortisol can increase blood cholesterol, triglycerides, blood sugar, and blood pressure, all of which increase cardiovascular disease risk.
If you don’t want a pet, you of course shouldn’t get one: Having to clean the litter box of a cat you’re not interested in taking care of or having to walk a dog you don’t desire could cause increased stress rather than stress reduction. But if you’re on the fence about getting one, the accumulating evidence of health benefits may help sway your decision. It could well be a win-win situation for both you and the pet, especially if it’s an animal from a shelter or rescue group.
This article first appeared in the UC Berkeley Wellness Letter.
Also see Pawsitive Thinking.