There are a few things that are distinct to every person—her fingerprints, voice, particular way of walking, and, it turns out, the way she chews. Mary Roach’s new book, Gulp, takes readers on the same trip their food goes, and she writes that your way of chewing is unique to you:
The way you chew, for example, is as unique and consistent as the way you walk or fold your shirts. There are fast chewers and slow chewers, long chewers and short chewers, right-chewing people and left-chewing people. Some of us chew straight up and down, and others chew side-to-side, like cows. Your oral processing habits are a physiological fingerprint.
Of course, there are all sorts of people telling you how to chew. Some places say that the way you chew can help you diet better or be healthier. The best way to chew for weight loss is excessively, to burn calories. (Seriously, that is a tip.) Chewing for longer can also make you feel like you’ve eaten more food than you really have and can give your body time to process the “full” signals it’s sending you. This is why many diets suggest chewing gum to fool yourself into thinking you’re eating. (A new study, though, found that chewing minty gum can actually prompt people to eat sugary snacks and junk food instead of fruits and vegetables.)
Roach offers all sorts of other strange insights into our chewing prowess in the excerpt published in the New York Times. Like, for example, this gem about why food crunches:
For a food to make an audible noise when it breaks, there must be what’s called a brittle fracture: a sudden, high-speed crack. Dr. Van Vliet takes a puffed cassava chip from a bag and snaps it in two.
“To get this noise, you need crack speeds of 300 meters per second,” he said. The speed of sound. The crunch of a chip is a tiny sonic boom inside your mouth.
So the next time you sit down for lunch, take note of the tiny sonic booms in your mouth, the uniqueness of your munching and the strangeness of the human digestive tract.
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