What Causes Hiccups?

Your Diaphragm and Breathing

Normal breathing is an involuntary action, meaning your brain does it for you without you having to think about it. Your brain controls breathing by telling the diaphragm to contract and relax. When the diaphragm contracts, it lowers, which creates more room in your lungs allowing them to fill with air. When your diaphragm relaxes, it rises up against the lungs pushing air out of them.

Your Diaphragm and Hiccups

When you're resting, your diaphragm comfortably contracts and relaxes about 20 times a minute. But sometimes your diaphragm gets an error message that results in a sudden contraction of your diaphragm. This split-second contraction draws air into your lungs very quickly, and when that air passes over your vocal cords, it causes the funny 'hic' sound.

Causes and Treatments
The exact cause of the error message that results in hiccups is not well-understood. However, hiccups are more likely to appear if you eat too fast or too much, drink soda or other carbonated beverages, swallow air, or experience a strong emotion like excitement or stress