Get a Pet, Get Healthy?

Recent research raises questions about health benefits.

Posted Apr 21, 2018

Gail Melson
Source: Gail Melson

The health promoting benefits of pet ownership have been touted widely and are now widely accepted. Dogs get you outside walking, revving up the heart and shedding excess pounds. Pet owners have been shown to access doctors less frequently (an indirect marker of physical health). When reading aloud in the presence of a friendly dog, not necessarily one’s own pet, blood pressure and heart rate are lower than when reading aloud in the presence of a good friend. Pet owners report feelings of social and emotional support. A current theory for how pet ‘medicine’ works hypothesizes that being with one’s loved animal releases the hormone oxytocin, associated with feelings of calm and well-being. Animal assisted therapy as well as animal-assisted activities such as hospital visits with dogs, rest on the assumption that being with a friendly animal (usually but not limited to dogs) promotes greater physical and emotional well-being.

However, a 2017 study in PlosOne called attention to an important limitation to our current knowledge about the impact of pet ownership on health. Because it is difficult, if not impossible, to randomly assign pets to people (it is not clear that would be ethical), selection factors may play an important role in people acquiring pets and living with them. If so, it is difficult to tease out pet ownership from its confounding variables. This is a particular problem, since many of these variables are associated with health outcomes.

Who gets pets anyway? The PlosOne study examined a large, representative sample of California residents who responded to the 2003 California Health Interview Survey. Over 42,000 adults were queried. The sample reflected the diverse California population in terms of social class, race, ethnicity, geography, age and family composition. About 46% of all the adults were living with either a dog or cat or both. This confirms how widespread pet ownership is and points to its potential importance.

It turned out that pet owners were indeed different from non-pet owners in ways that might impact health. Pet owners were more likely to be married, female, white, living in a house rather than an apartment, living in a rural rather than urban area, and employed full time. Some of these demographic differences were dramatic, others were relatively small differences. For example, adults self-identifying as “white” were three times as likely as adults of other races to be living with a dog. By contrast, married adults were only 34% more likely to be dog owners than were non-married adults. Health outcomes for minorities and for non-married adults are known to be less positive. Thus, if pet ownership is associated with better health, it may be because healthier individuals become pet owners (and perhaps stay pet owners) in the first place.

Now that we know more about how pet owners (at least in California) differ from non-owners, future research can statistically control for these demographic differences. Another takeaway from the PlosOne study suggests that we study pet ownership in a more fine-grained way. Relatively little research focuses on racial and ethnic minorities and their experiences with pets. In addition, health indicators for pet owners and non-pet owners can be more directly assessed. Perhaps experiencing ill health discourages people from taking on the responsibility and expense of pet ownership. On the other hand, the widespread view that pets make one feel better might prompt people who feel depressed or lonely or suffering from illness to welcome pet ownership.

Finally, pet ownership is a crude measure of one’s experience living with a companion animal. People develop different relationships with their pets, just as people develop varied relationships with relatives, friends and neighbors. Measuring the quality of this pet relationship, rather than simply the binary fact of pet versus no-pet, is likely to be a more sensitive measure of a pet’s potential to cure what ails you. Meanwhile, don’t assume that bringing a dog or cat into your home will be the ‘magic bullet’ making you healthier physically or emotionally. On the other hand, while we are waiting for definitive results, those animals just might do the trick.

References

Saunders, J., Parast, L., Bebey, S., & Miles, J. V. (2017). Do pets make us healthier? Selection factors lead to pet ownership. PlosOne 12, e0179494. https://doi.org/10.1371/journal.pone.0179494.