The Study

Our study will explore whether dogs might enhance human health and well-being, in part, by working as probiotics in older people by enhancing their overall health. The research is being sponsored by Fintech Ltd as part of the company’s science contribution program.

Dogs as Probiotics for People

We think dogs might work as probiotics to enhance the health of the bacteria that live in our guts. These bacteria or the “microbiota”,  are increasingly recognized as playing an essential role in our mental and physical health, especially as we age.

Everyone knows dogs are “man’s best friend.” But have you ever wondered, in addition to this emotional bond we have with dogs, whether there is a biological component that actually improves the health of both dogs and humans? These are the questions being explored in a novel study we are currently planning at the University of Arizona’s Department of Psychiatry in partnership with the Humane Society of Southern Arizona and colleagues at the University of Colorado at Boulder.

Why the Microbiome is Important

Thanks to recent advances in science, we know that the majority of the bacteria in our guts are an essential part of our ecosystem and are vitally important to maintaining all aspects of our physical and mental health. We know that not all bacteria are good; we can get very sick from the “bad” bacteria, and modern medicine has done a wonderful job of protecting us from various diseases that are created by these bacteria. But unfortunately, it seems, that by eliminating the bad bacteria we’ve started eliminating the “good” bacteria too.

This “good” bacteria can be thought of like a “probiotic”. Through research, we’ve learned that people who own dogs are much more likely to share the same kinds of these “good” bacteria with their dogs. (5) We have also learned that children who are raised with dogs are less likely than others to develop a range of immune related disorders, including asthma and allergies.(2,3,4) Suggesting that maybe dogs are enhancing the “good” bacteria in our bodies, and possibly improving our health.

We’ve all heard about probiotics through pills and yogurt, but what if owning a dog had the same effect on us? And what if they help improve the immune systems of the whole family?

Understanding the Microbiome Connection Between Older People and Dogs

We are doing this study in older adults specifically to see if the changes science has shown for children can be replicated in older people, and to see if dogs can improve the physical and mental health of these adults.

If dogs act as a sort of probiotic for dog owners, is it possible that they can have this same effect on people who haven’t lived with a dog ever or for a long period of time? In addition to bacteria, dogs are just great companions, so we are also interested in looking at whether the introduction of a dog into the home of older adults improves their sleep, their muscle and bone strength, their ability to move around, and their overall happiness and quality of life.

How can I get involved?

Participate in the Study as a Volunteer!!

For more information on participating in this study, please see the ‘potential participants’ page on this website.


You can help us find out by donating to our campaign: For a 100% tax deductible donation, you can visit this University of Arizona donation page.

Click here for a short video detailing our study


(1) Kuningas, M., L. May, R. Tam et al.2009 Nov 11;4(11):e7795. doi: 10.1371/journal.pone.0007795. Selection for genetic variation inducing pro-inflammatory responses under adverse environmental conditions in a Ghanaian population.

(2) Almqvist, C, a-C Egmar, G Hedlin, et al. 2003 Direct and Indirect Exposure to Pets – Risk of Sensitization and Asthma at 4 Years in a Birth Cohort. Clinical and Experimental Allergy : Journal of the British Society for Allergy and Clinical Immunology 33(9): 1190–7.

(3) Havstad, Suzanne, Ganesa Wegienka, Edward M Zoratti, et al. 2011 Effect of Prenatal Indoor Pet Exposure on the Trajectory of Total IgE Levels in Early Childhood. The Journal of Allergy and Clinical Immunology 128(4). Elsevier Ltd: 880–885.e4., accessed September 8, 2014.

(4) Ownby, Dennis R, Christine Cole Johnson, and Edward L Peterson 2002 Exposure to Dogs and Cats in the First Year of Life and Risk of Allergic Sensitization at 6 to 7 Years of Age. JAMA : The Journal of the American Medical Association 288(8): 963–72.

(5) Song, Se Jin, Christian Lauber, Elizabeth K Costello, et al.
2013 Cohabiting Family Members Share Microbiota with One Another and with Their Dogs.