New Study: Living With a Dog May Lower Dementia Risk

A new study involving more than 11,000 older adults in Japan suggests people who currently lived with a dog had a 48 percent lower risk of developing disabling dementia compared to people who had never owned a dog.

While this is a striking finding, it comes with an important qualification: the study does not prove that having a dog prevents dementia. However, it does suggest that living with a dog is a positive contributary factor.

The research, published in the International Journal of Environmental Research and Public Health, followed 11,224 community-dwelling adults age 65 and older for approximately 7.5 years. Participants were classified as current dog owners, former dog owners or people who had never owned a dog. Researchers then tracked the development of disabling dementia through Japan’s long-term care system.

During the study, 17.7 percent of all participants developed disabling dementia. Among current dog owners, 12.8 percent developed dementia, compared with 18.1 percent of people who had never owned a dog.

This isn’t the first time these Japanese researchers have found a connection between dogs and dementia.

A 2023 study involving 11,194 older adults, published in Preventive Medicine Reports, followed participants for about four years. Current dog owners had approximately 40 percent lower odds of developing disabling dementia than people who were former or never dog owners.

Dogs Are Associated with Social Interactions and Exercise

The apparent benefit was particularly pronounced among dog owners who exercised regularly or were not socially isolated. In other words, the dog itself may not be the entire story.

Walking a dog gets people moving. Caring for a dog creates a daily routine. And taking a dog outside can create opportunities for social interaction with neighbors and other dog owners. Physical activity, social engagement and maintaining routines are all significant factors researchers have investigated in connection with healthy cognitive aging.

There is also some evidence that the relationship may be specific to dogs and dog-related activities. A 2026 systematic review published in the American Journal of Medicine examined six studies looking at pet ownership and dementia or cognitive decline. Two studies suggested a protective association, particularly involving dogs, while another found no significant association. The review concluded that the type of pet and what people do with their pets may be more important than simply owning an animal.

Dogs as a Prescription?

Overall, recommending pet ownership specifically to prevent dementia would be premature. Having said that, there does seem to be some correlation. Then again, correlation doesn’t always mean causation.

Still, this newest study provides additional evidence that the relationship may be more than simply a coincidence.

The dog may not be a prescription for preventing dementia. But daily life that comes with a dog can support physical activity, social interaction and a sense of routine; we know these things may contribute to healthy aging. And perhaps the dog himself or herself deserves a little credit, too.