It appears they didn't control for folks who lived together or had begun open-mouth kissing before marriage. Am I missing something?

The study says sleep quality is also affected. I have doubts about this transmission mechanism, but it is an idea made for speculative fiction with a Gothic tinge. It's like a light version of vampirism without all the blood: they kiss you (for a while), and you become morose and nocturnal.

After reading I’m confused how oral bacteria is shown to be the cause. What I’m reading is that moving in with a depressed person is depressing.

They cite work showing that "oral microbiota dysbiosis is significantly correlated with various neuropsychiatric disorders, including autism spectrum disorder, dementia, Parkinson’s disease, schizophrenia, anxiety, epilepsy, and depression."

No claims are made that oral microbiota cause depression and anxiety. I find it easy to believe that after marriage, couples converge in depression and anxiety absent any kissing. And because of kissing, their oral microbiota will also converge. But that doesn't imply that kissing is the cause of the convergence in depression and anxiety. Maybe I am missing something.

HNed//.ed

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