You know the feeling. You're taking a drink or eating a bite of food and suddenly you start choking and gagging and gasping for air. Something obviously went down the wrong pipe.

We've all experienced the miserable sensation, but what exactly causes it?

When you swallow food or drink, what's supposed to happen is it moves from your mouth, through your throat, down your esophagus, and into your stomach. The process seems easy and you do it without thinking, but the reflexive act of swallowing actually involves 30 muscles and nerves.

Along the way, there's a leaf-shaped flap of tissue at the base of the tongue called the epiglottis that keeps food from going into the windpipe (officially the trachea) when you're swallowing. At the same time, the vocal cords close tight to help seal the airway and the hyoid bone and larynx (voice box) are pulled upward and forward and your esophagus opens up. Breathing pauses briefly as swallowing happens.

Sometimes, however, this whole system doesn't work as it should with the epiglottis or vocal cords not closing properly. That's when the food or liquid you're trying to swallow "goes down the wrong way" and ends up becoming inhaled into your windpipe or lungs. This is called aspiration, says WebMD.

It's normal for people to occasionally aspirate microscopic amounts of food or liquid, according to an article on swallowing disorders in the journal American Family Physician. It doesn't feel great, of course, and the body's reflex is to cough (sometimes violently) and often that will help clear out the problem. Problem solved and you can return to swallowing the normal way.

But aspiration can become serious if food makes its way into your lungs. It can lead to lung inflammation and even pneumonia. It can be especially irritating and potentially dangerous if you were eating or drinking something acidic like orange juice, because acidic items tend to be the most damaging to the lungs and can lead to pneumonia.

Sometimes people don't have the immediate reflex to cough or gag when food or liquid is heading into the trachea or lungs. This is called silent aspiration and can lead to serious respiratory issues. It's more common in people with swallowing problems, called dysphagia. People can have problems swallowing when muscles become weak due to illness, injury or aging.

Aspiration in general tends to be a problem with kids under 3 and adults over 50, according to WebMD. But anyone can have it happen once in a while. If your wrong-pipe problems are occasional, slow down and cough when you need to. If you find yourself constantly hacking after you try to swallow, you may want to consider visiting an ENT to make sure there's nothing else going on.

Mary Jo DiLonardo Mary Jo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.