Why Does My Stomach Growl?The Gut's Housekeeping Wave

It always seems to happen in the quietest moment of a meeting or a yoga class. Most of the time, the sound is simply your gut doing its job.¹

The housekeeping wave

Between meals, your stomach and small intestine run a repeating cycle of contractions called the migrating motor complex.² Its strongest phase can start in the stomach or the small intestine and sweeps contents along.² It’s been called the “housekeeper of the gut,” because problems with it were linked to bacterial overgrowth in the small intestine.²

Is a growl a hunger signal?

Researchers in Belgium measured contractions and hunger in fasting volunteers:³

Phase of the wave	Average hunger rating
Quiet phase	About 273
Middle phase	About 373
Strongest phase, starting in the stomach	About 633

When a drug triggered the strong stomach phase early, hunger jumped from about 29 to 62.³ People with unexplained loss of appetite lacked that phase.³ The authors concluded the stomach’s strong contractions are a hunger signal.³

The study measured contractions and hunger, not sound. So a growl may come from this wave, but not every growl means you’re hungry.

Can anyone tell what a growl means?

Not by listening. In one study, 41 clinicians heard recordings of gut sounds from healthy people and from patients with a blocked or stalled bowel, without knowing which was which.⁴ They correctly identified the normal recordings only 32% of the time, and the authors concluded listening to gut sounds isn’t a useful way to tell normal from abnormal.⁴

When sounds are normal

• Gut sounds get louder after eating or with diarrhea.¹
• They go quiet during sleep.¹
• Most are harmless and need no treatment.¹

When to check

Contact a doctor if gut noises come with:¹

• Bleeding from your rectum
• Nausea or vomiting
• Diarrhea or constipation that continues

Get urgent help for severe belly pain, a swollen belly with vomiting, or being unable to pass gas or stool.

In the moment

A loud stomach is ordinary. A small snack before a long, quiet meeting may help if hunger is the trigger; if gas is involved, see how much gas is normal and gas and bloating at work and home.

Try: “My stomach gurgles loudly most afternoons, and lately I’ve had some loose stools too. Is this worth looking into?”

Bloated by Dinner covers this in Chapter 5, “Ten to Twenty a Day,” in a section called “The Housekeeping Growl.” Its Belly Clock logs when sounds, gas and meals happen over one to two weeks, so you can see whether the noise follows hunger, food or something else. See the book.