Are Dog Mouths Cleaner Than Human Mouths?

Are Dog Mouths Cleaner Than Human Mouths?

It's a common misconception that dog mouths are cleaner than human mouths. Both mouths are hosts to hundreds of kinds of bacteria, most of which are species-specific. There's only about a 16% overlap of oral microorganisms between dogs and humans, so there's no such thing as comparable, objective "cleanliness" with regards to their mouths.


Key Facts In This Video

  • 1

    Dog mouths are not cleaner than human mouths, as both mouths contain species-specific bacteria. (0:43)

  • 2

    One 2015 study found that oral-to-oral transfer of bacteria from dogs to humans can cause gingivitis and periodontal disease. (1:14)

  • 3

    You're more likely to catch an infection by swapping saliva with another human than with a dog. (2:37)

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