My hypothesis is that the reason younger people get health benefits from pets, while old people “in a community” do not, is that the younger people spend more time outdoors walking their dogs, gaining both cardio benefit and exposure to sun which generates vitamin D. Old people let someone else walk the dog, or they have a doggy door, or they simply own a cat.

Interestingly, vitamin D confers similar health benefits as pet ownership, and most people don’t get enough of it. Is it just a coincidence?

One way to test, albeit not conclusively, the reason pet owners are healthier than non-owners is to see if cat owners get the same health benefits as dog owners. My hypothesis is that cat owners get less sunlight, and less cardio, because you typically don’t walk a cat.

Some of the health differences, if any, might be because dog owners are hardier people than cat owners to begin with. If you’re not too healthy, and want a pet, you get a cat before you get a dog. So that would have to be factored in.

All I know for sure is that since I got my first dog, I’m getting all sorts of sun exposure that I wouldn’t normally get, in small doses throughout the day. And I also get about an hour of walking per day, cumulative, that I wouldn’t otherwise get. My cats give me none of those potential benefits.

So the testable hypothesis is that most of the health benefits of pet ownership are associated with dog owners, not cat owners, and the reason has to do with the walking of the dog more than the emotional bonding, although the latter might have some health benefits too.

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