11 Surprising Facts About the Digestive System

Physicians treated peptic ulcers incorrectly for nearly a century.

An illustration of a stomach

(Image credit: Stomach ulcer illustration via Shutterstock)

Peptic ulcers are painful sores on the lining of the esophagus, stomach or small intestine, and they affect approximately 50 million Americans each year, according to a 2007 study in the journal American Family Physician.

Physicians long thought that stress and spicy food caused people to develop the sores — an explanation that seemed to make sense, given that ulcer patients often complain about burning pain after eating spicy food. So for almost 100 years, doctors prescribed a treatment involving rest and a bland diet.

In 1982, Australian researchers Barry Marshall and Robin Warren discovered that the real culprit behind ulcers is the bacterium Helicobacter pylori, which burrows into the stomach's mucosal lining. Thanks to this finding, doctors have come up with a better treatment for ulcers: antibiotics.

This discovery earned Marshall and Warren the Nobel Prize in Physiology or Medicine in 2005.

Stomach rumbling can happen at any time, not just when you're hungry.

stomach cramps

(Image credit: Piotr Marcinski | shutterstock)

Borborygmi, or stomach rumblings, are the result of peristalsis in the stomach and small intestines — that is, they're due to normal digestion as food, fluid and gases pass through your gastrointestinal tract. When the tract is empty, however, borborygmi are louder because there's nothing in there to muffle the sound.

So why are the muscles contracting at all when there's no food in the stomach?

After the stomach empties its contents into the small intestine, it sends signals to the brain. The brain responds by telling the digestive muscles to commence the process of peristalsis. The muscle contractions ensure that no excess food was left in the stomach, and the resulting growls signal to you that your body needs food.

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Joseph Castro
Live Science Contributor
Joseph Bennington-Castro is a Hawaii-based contributing writer for Live Science and Space.com. He holds a master's degree in science journalism from New York University, and a bachelor's degree in physics from the University of Hawaii. His work covers all areas of science, from the quirky mating behaviors of different animals, to the drug and alcohol habits of ancient cultures, to new advances in solar cell technology. On a more personal note, Joseph has had a near-obsession with video games for as long as he can remember, and is probably playing a game at this very moment.