Why do we hiccup?
(Lansing State Journal, December 20,1995)
The diaphragm is the large dome shaped muscle under the lungs that aids in breathing. At times, the diaphragm may become irritated. Similar to a muscle twitch, the diaphragm will start to spasm and contract uncontrollably. With each contraction, air is pulled into the lungs very quickly. The air passes through the larynx, or voice box. The epiglottis closes behind the rush of air, shaking the vocal chords. This shaking makes the familiar "hic" sound.
A spasm of the diaphragm can be caused by many things. Rapid eating, emotional stress and even some diseases can irritate the diaphragm and cause hiccups.
Many popular remedies to cure the hiccups exist. Breathing into a paper bag, the best remedy, increases the amount of carbon dioxide in the lungs, relaxing the diaphragm and halting the spasms.