The Science of Hiccups

"Here's What's Happening When You Hiccup":

Cameron explains that the hiccups are caused when your diaphragm contracts—initiating an intake of air—while, at the same time, your vocal cords close, stopping the air from getting to your lungs. The closure of your vocal cords is, according to Cameron, what’s causing that annoying hiccup sound. Cameron also notes that scientists have diverging theories on why humans hiccup: Some believe it helps nursing babies keep milk out of their lungs, while others think hiccups got their start millions of years ago, before animals even made the transition from water to land. Whatever the cause, Cameron makes one thing very clear: There’s still no known cure.

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