Mouth breathing through the night can lead to diminished sleep quality, snoring and elevated stress.

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CNN  — 

Living with a plugged nose isn’t fun, but James Nestor was ready. Plus, it was for science.

While researching his book, “Breath: The New Science of a Lost Art,” Nestor let Stanford University scientists block his nostrils with silicone and surgical tape to measure the impacts of breathing through his mouth for 10 days.

“We knew it wasn’t going to be good, because there’s a very firm scientific foundation showing all the deleterious effects of mouth breathing, from periodontal disease to metabolic disorders,” Nestor said.