Stomach
(Photo : Pixabay / derneuemann)

Did you ever hear your stomach growl when hungry? This is actually quite a normal experience.

Interestingly, the stomach may also growl even when it's full.

Stomach Growling When Hungry

Peristalsis could explain why one may hear their stomach growling when hungry. The muscle contractions that are part of this process mainly focus on the propelling of liquids, gas, and food in the digestive tract.

In order to enable food to reach the other end, sequential contractions happen in the muscles built into the tube's lining. One set of muscles contracts after the other. This ends up pushing digestive contents as it goes.

Borborygmi, or stomach rumbling sounds, could happen because of these contractions. The sounds could be more audible when a person is hungry.

Ghrelin, a type of hormone, is released when the stomach stays empty for hours. When ghrelin reaches the brain, it causes hunger feelings and triggers peristalsis.

The stomach and intestine contract even when devoid of food. This is possibly done in order to cleanse the intestines or stomach from remaining microbial, solid, or liquid debris.

Compared to when the digestive tract is full, such peristalsis is slower. It may only take place every 20 minutes.

Because more air is present compared to solid, the rumblings could be more frequently heard when the digestive tract does not have any food.

However, people can also experience stomach rumbling even when they don't feel hungry.

ALSO READ: Gastrointestinal Transit: How Long Does It Take To Digest Food?

Peristalsis Could Cause Rumbling on a Full Stomach

According to Tiffany Weir, a food science and human nutrition professor from Colorado State University, the stomach can growl when hungry or full. This is due to the fact that humans have hormones that regulate appetite, which could cause peristalsis.

Right after having a meal, a lot of peristalsis happens. On average, the stomach sees around three waves per minute. It may also see 12 waves across the small intestine.

With food getting pushed across the digestive tract, it ends up getting churned and mixed to facilitate digestion. The process of having liquids and solids mixed together is not silent.

In most cases, this action of peristalsis may not be noticed due to how the intestines and the stomach muffle sounds made by the digestive tract.

Digestive Issues

In certain cases, digestive issues could also trigger stomach growling.

Some digestive conditions, such as gastroenteritis, could cause diarrhea, which is a condition that involves increased action of peristalsis to clear the intestines. This could also be noisy at times.

Incomplete food digestion of certain foods, such as dairy products and beans, could also lead to the production of surplus gas. This could end up exacerbating peristalsis sounds.

Overall, with digestive issues taken aside, it is common and harmless for stomach growling when hungry or full to happen. It is a typical side effect of the function of the human digestive system.

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