Breath

In Japan, legend has it that samurai would test a soldier’s readiness by placing a feather beneath his nostrils while he inhaled and exhaled.

Exactly a year to the week after I began wearing Belfor’s retainer, I visited a private radiology clinic in downtown San Francisco and had my airways, sinuses, and mouth rescanned. Belfor sent the results to AnalyzeDirect at the Mayo Clinic to study what had happened to my face and airways.

Today, the official website of the U.S. National Institutes of Health attributes the causes of crooked teeth and other deformations of the airway “most often to heredity.” Other causes include thumb-sucking, injury, or “tumors of the mouth and jaw.”
There is no mention of chewing; no mention of food at all.