Ask a grown-up: why do people get hiccups?
We know how we get hiccups (or hiccoughs), but not why. Hiccups occur when the diaphragm (our breathing muscle) contracts suddenly. The contraction is a reflex (like the jerk that occurs when a doctor taps the knee with a hammer) that may be started by a local irritation. The irritation often comes from the stomach, which is close to the diaphragm. The irritation may be from food, especially if eaten too fast, or by gas from a fizzy drink, but often there is no obvious cause.
Tadpoles hiccup to breathe, and some people think this is a hangover from our tadpole past; as babies, we hiccup before we are born. And hungry babies who feed too quickly hiccup, which may help them empty the stomach of air, making room for more milk. Though your dad told you hiccups are caused by naughtiness building up inside you, nobody has ever found naughtiness to be a cause: your dad needs a biology lesson.
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