Do Pets Protect Against Dementia? The Honest Answer Is 'Maybe'

We read the abstract, and the most useful thing in it is what the authors would not say.

A 2026 systematic review in The American Journal of Medicine asked a simple question: does owning a pet lower your risk of dementia? The authors searched five databases (PubMed, Embase, CINAHL, Web of Science, and PsycINFO) for prospective studies of adults without dementia. They found six. Only three of those actually tracked new dementia cases, and the studies were too few and too different from one another to pool into a single number. So the authors did not run a meta-analysis. They did a narrative synthesis instead: they described the studies rather than combining them.

The picture that came back was mixed. Two of the studies suggested a protective link, dog ownership especially, but the others did not line up neatly behind that result. So the honest summary is not “pets prevent dementia.” It is closer to this: a real question that nobody has yet studied enough to answer.

That restraint is the point. The internet is full of confident headlines claiming a dog will guard your brain. A review whose main finding is “the evidence is too sparse to conclude” is more useful than any of them, because it tells you the truth about where the science actually stands.

None of this means the bond is imaginary. Other research has measured it more carefully in narrower lanes. A 2023 JAMA Network Open study of nearly 8,000 UK adults over 50 (Li et al.) found pet owners showed slower cognitive decline — but only among people living alone, where companionship may matter most. That is a specific, bounded finding, not a blanket promise.

So if you have wondered whether your dog or cat was good for your mind, the answer the evidence supports is a careful “maybe, especially if you live alone” — and anyone telling you more than that is getting ahead of the data.