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Human body

Why do we have hiccups?

Vocal cords in the closed positionVocal cords in the closed positionA hiccup is an involuntary contraction (tightening) of the diaphragm, the sheet of skeletal muscle that lies under the rib cage and helps to control breathing. Normally, when you inhale (breathe in), the diaphragm pulls down, helping to suck air into the lungs. When you breathe out (exhale), the diaphragm relaxes, the lungs are squeezed, causing air to be pushed back out through the nose and mouth. Sometimes, however, the diaphragm becomes irritated. It jerks downwards—often at regular intervals—making you suck air into your throat suddenly. When this incoming air meets your voice box, the vocal cords close, making a “hic” sound.

Breathing in (left) and out (right)Breathing in (left) and out (right)Click to play video

Causes of hiccups

No one knows quite why hiccups occur. Most cases of hiccups come after eating or drinking too much or too quickly. Some people get them after drinking fizzy drinks or eating spicy food. In rare cases, hiccups can last for a long time. If they last longer than a month they are called "intractable", and are linked with certain medical conditions.

Breathing into a paper bagBreathing into a paper bag


Hiccups may also be spelled "hiccoughs”.

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