Does owning a dog lower the risk of dementia?
— The latest research connecting social isolation, motor function, and brain health —
You may have heard that "owning a dog makes you less likely to develop dementia."
In recent years, scientific reports on the effects of dog ownership and walking habits on health have been increasing, including studies targeting elderly Japanese people.
However, the important point is that it has not been proven that "dogs themselves protect the brain".
When organizing the latest research, the keys are
a reduction in social isolation
the maintenance and improvement of motor function
changes in dementia risk associated with these
which are "changes in lifestyle behavior."
In this article, we will explain what is scientifically known in an easy-to-understand manner based on representative research.
Reduction in social isolation — Dogs create a "reason to go outside"
What changes with dog ownership is not just comfort, but lifestyle behavior.
A study by Curl et al. (2020) reported that dog ownership is associated with elderly people's interactions with neighbors and their outdoor activities. Dog walking is considered a natural trigger for communication and is likely to create connections with the community.
In the study,
frequency of going out
interaction with neighbors
social engagement
clear associations were seen in behavioral aspects such as these.
Social isolation is considered to be strongly related to the risk of dementia, and going out and interacting through dogs may consequently lead to lifestyle habits that support brain health.
Improvement in motor function — Dog walking changes the body
In a study by Gallagher et al. (2025), elderly people who walk their dogs regularly have:
better mobility (TUG test)
a lower risk of falling
Less fear of falling
This characteristic has been reported.
In old age, having a 'reason to walk' significantly impacts the maintenance of physical function.
Walking a dog
aerobic exercise
maintenance of balance ability
improvement of lower limb muscle strength
naturally encourages these in daily life.
In other words, the key is to make 'sustainable low-to-moderate intensity exercise' a daily habit.
For dog owners, this happens 'naturally and inevitably'.
Lower dementia risk — What a Japanese longitudinal study showed
A longitudinal study by Taniguchi et al. (2023) on elderly Japanese people reported that dog owners have a lower risk of developing dementia requiring long-term care compared to non-owners.
However, it is not accurate to interpret these results simply as
'owning a dog prevents dementia'.
It is not accurate to interpret it that way.
In the study, the risk reduction was particularly significant for
people with exercise habits
people with less social isolation
the risk reduction was significant.
In other words, rather than dogs directly lowering dementia risk as in the aforementioned study, it is more likely due to
increased physical activity from walking
social participation through going out and interacting with others
It is considered highly likely that such changes in lifestyle habits are associated with the risk of dementia.
Common points seen from three studies
Summarizing these studies, the common thread is the following sequence:
Owning a dog increases opportunities for going out and taking walks
Physical activity levels increase, improving mobility and reducing fall risk
Social interaction increases, reducing isolation
✅These lifestyle factors are associated with a lower risk of dementia
In other words, rather than the dog being the "cause of health," it is more scientific to view it as a catalyst for maintaining a healthy lifestyle.
Why were the same results not seen with cats?
In this study, analysis was conducted not only on dog ownership but also on cat ownership. However, no significant association was confirmed between cat ownership and the risk of developing dementia (odds ratio 0.98, 95% CI: 0.62–1.55).
The background for this difference is thought to be changes in daily behavior. Dog ownership requires daily walks, which naturally increases physical activity and opportunities to go out. On the other hand, cat ownership tends to be centered indoors and is not necessarily linked to an increase in exercise habits or social interaction.
Therefore, it has been pointed out that factors thought to be involved in lowering dementia risk, such as increased blood flow from physical activity and stimulation from going out, may not have been sufficiently generated.
Summary: It is not the dog, but an "active lifestyle" that protects the brain
What has emerged from the latest research is a simple conclusion.
It is not that dogs directly prevent dementia, but rather that the lifestyle of "moving," "going out," and "interacting with people" that dogs create may be associated with brain health as a result.
Even if you do not own a dog,
daily walking habits
community interaction
regular outings
are just as important.
Protecting brain health may not require special methods, but rather the accumulation of daily habits.
📚References
Taniguchi Y, et al. Protective effects of dog ownership against the onset of disabling dementia in older community-dwelling Japanese: A longitudinal study. Preventive Medicine Reports. 2023;36:102465.
Curl AL, Bibbo J, Johnson RA. Neighborhood engagement, dogs, and life satisfaction in older adulthood. Journal of Applied Gerontology. 2020.
Gallagher E, et al. The Association of Regular Dog Walking with Mobility, Falls and Fear of Falling in Later Life. The Journals of Gerontology Series A. 2025.