The astronomer Carl Sagan famously cautioned, “Extraordinary claims require extraordinary evidence.” I recently came across an extraordinary claim by Beth Frates: "Pet owners are less likely to die.”
Frates is a lifestyle physician at Harvard’s T.H. Chan School of Public Health, and her surprising statement appeared in a Harvard Magazine article. Everyone, of course, dies. But is it possible that owning a pet adds years to your life?
Frates' claim was based on a reputable source—a peer-reviewed paper in the American Heart Association journal, Circulation: Cardiovascular Quality and Outcomes. In it, a research team headed by Caroline Kramer of the University of Toronto reported that dog ownership is associated with a whopping 24 percent decrease in mortality rates.
Too Good to Be True?
The idea that adopting a puppy will help you live longer is appealing—but did the results of the study meet Sagan’s extraordinary evidence bar? The research was a meta-analysis of studies on the association between dog ownership and death rates. Meta-analysis is a statistical technique in which investigators combine the results of multiple studies on the same topic—in this case, studies comparing the death rates of dog owners and non-owners.
The media jumped on these findings, err, like a dog on a bone. A CBS News headline read, “Dog Ownership Linked to 24 Percent Lower Risk of Dying Early." However, the authors of the study made a serious mistake in their analysis—they did not take into account that pet owners are different from non-owners in many ways.
For example, in a study of 22,000 pet owners and 19,000 non-owners by the Rand Corporation pet owners tended to be younger, wealthier, and more educated than non-pet owners. Pet owners were also more likely to be White, married, have children, own their own home, and have better general health. Once the researchers plugged these variables into their analysis, the presumed benefits of pet ownership on physical health vanished. (See Large Study Finds Pet Owners Are Different.)
Other researchers quickly pointed out methodical errors in the meta-analysis published by the American Heart Association. A team headed by Adrian Bauman of Sydney University reanalyzed the results of the studies used in the original paper. Their improved meta-analysis subsequently appeared in the journal. When demographic and socioeconomic differences between dog owners and non-owners were included in their analysis, Brauman’s group found there was not a significant association between pet ownership and mortality rates.
I was intrigued by these conflicting findings and took a deep dive into the studies on pet ownership and death rates. I searched for population-based epidemiological studies in which owners and non-owners were followed over time. I found nine studies published in peer-reviewed publications between 2010 and 2023. In comparing the death rates of pet owners and non-owners, all of them statistically controlled for confounding variables such as sex, age, and chronic medical conditions. And, ranging from 4,000 to 3.5 million participants, they were very large. (The median number of subjects in the studies was 59,342 individuals.)
The Truth About Pets and Death
Here are the results of the studies in chronological order.
Most Studies Have Not Found Pet Owners Live Longer
An editorial by Harvard Medical School's Dhruv Kazi accompanied the flawed 2019 meta-analysis. He wrote that, because the link between dog ownership and mortality has been found across many countries and populations, "it is safe to assume that the association is real."
However, the only population-based research that reported differences in death rates between pet owners and nonowners was from Scandinavia, the two studies from Tove Falls' group in Sweden and the study in Denmark that found lower mortality in dog owners without a spouse. Indeed, among European Union nations, countries in which people live longer, tend to have lower—not higher—rates of dog ownership. (For stat nerds, r = -.42).
In an email, Fall suggested a possible explanation for these results: "Scandinavian dog owners might be a bit more dedicated as animal welfare laws are strict here. If you are among the few selected who get a dog, you walk the dog and maybe are more likely to have the health to do it. There are many publically accessible green areas here. Another aspect is that our results are mainly driven by the association in single households. On a global scale, Sweden has a high proportion of single-households—the most common form of household in the country according to Eurostat. On a European scale, Sweden is number one on this list and Denmark number three."
Does research support the contention that pet owners are less likely to die? If we take Carl Sagan’s warning that “extraordinary claims require extraordinary evidence," unfortunately the answer seems to be no, unless you live in Scandinavia.
References
Chowdhury, E. K., Nelson, M. R., Jennings, G. L. R., Wing, L. M. H., Reid, C. M., & Committee, on behalf of the A. M. (2017). Pet ownership and survival in the elderly hypertensive population. Journal of Hypertension, 35(4), 769.
Christopoulos, K., Benetou, V., Riza, E., & Pantazis, N. (2022). Pet ownership and survival of European older adults. European Journal of Ageing, 19(4), 1549–1560.
Ding, D., Bauman, A. E., Sherrington, C., McGreevy, P. D., Edwards, K. M., & Stamatakis, E. (2018). Dog Ownership and Mortality in England: A Pooled Analysis of Six Population-based Cohorts. American Journal of Preventive Medicine, 54(2), 289–293.
Gillum, R. F., & Obisesan, T. O. (2010). Living with Companion Animals, Physical Activity and Mortality in a U.S. National Cohort. International Journal of Environmental Research and Public Health, 7(6), Article 6.
Mubanga, M., Byberg, L., Nowak, C., Egenvall, A., Magnusson, P. K., Ingelsson, E., & Fall, T. (2017). Dog ownership and the risk of cardiovascular disease and death – a nationwide cohort study. Scientific Reports, 7(1), 15821.
Mubanga, M., Byberg, L., Egenvall, A., Ingelsson, E., & Fall, T. (2019). Dog Ownership and Survival After a Major Cardiovascular Event. Circulation: Cardiovascular Quality and Outcomes, 12(10), e005342.
Rådholm, K., af Geijerstam, P., Woodward, M., Chalmers, J., Hellgren, M., Jansson, S., & Rolandsson, O. (2023). Dog ownership, glycaemic control and all-cause death in patients with newly diagnosed type 2 diabetes: A national cohort study. Frontiers in Public Health, 11, 1265645.
Sørensen, I. K., Bidstrup, P. E., Rod, N. H., Rühling, T., & Johansen, C. (2018). Is dog ownership associated with mortality? A nationwide registry study. European Journal of Public Health, 28(6), 1169–1171.
Torske, M. O., Krokstad, S., Stamatakis, E., & Bauman, A. (2017). Dog ownership and all-cause mortality in a population cohort in Norway: The HUNT study. PLOS ONE, 12(6), e0179832.
login
who are we?
contact us
qosheapp
Toi Staff
Gideon Levy
Belen Fernandez
Rami G Khouri
Mort Laitner
Rachel Marsden
Donald Low
Bradley Blankenship
Ali Fathollah-Nejad
Nikkei Editorial
Abbas Juma
Michael Kwet
visit website
