The rumbling, gurgling sounds that come from your midsection are known scientifically as borborygmi. These noises are entirely normal and happen to everyone, often causing anxiety in quiet rooms about whether others can hear them. Stomach noises are a regular function of the gastrointestinal system, occurring whether you are digesting a meal or your stomach is empty. The intensity varies, but they indicate that your digestive tract is actively working.
The Science Behind Stomach Noises
The sounds you hear originate from the physical movement of the digestive tract, a process called peristalsis. Peristalsis involves wave-like muscle contractions that propel the contents of the stomach and intestines—a mixture of gas, liquid, and partially digested food—forward through the pathway. The resulting gurgle is the sound of this gas and fluid being squeezed and sloshed around by the contracting muscles.
These movements occur constantly, even when your stomach has been empty for several hours. When the stomach is empty, the brain triggers a specific type of cleansing contraction called the Migrating Motor Complex (MMC). The MMC acts like a “housekeeper,” sweeping through the stomach and small intestine to clear out remaining food particles, mucus, and bacteria. This activity, which occurs roughly every 90 to 120 minutes, is primarily responsible for the “hunger growls” associated with an empty stomach.
Why Growls Become Audible
While your digestive system is always producing noise, audibility depends heavily on the contents of your stomach and intestines. When the gastrointestinal tract is full of solid and semi-solid food, this matter acts as a physical muffler, dampening the sound of the moving gas and liquid. The dense food mass absorbs the vibrations, keeping the borborygmi internal.
When your stomach is empty, however, the process changes dramatically, allowing the sounds to resonate. The digestive tract becomes a hollow, open space where air and fluid are moved by muscular contractions with no food to absorb the vibrations. This emptiness creates an echoing chamber, similar to how sound travels through a hollow pipe, significantly amplifying the noise as it travels through the abdominal wall. The combination of vigorous MMC activity and a resonant, empty cavity is why others can sometimes hear your stomach growl.
When to Worry and Simple Ways to Quiet Your Gut
If you find yourself in a quiet environment, one of the quickest ways to temporarily quiet a rumbling stomach is to sip on some water. The water introduces new liquid into the empty stomach, which helps reduce resonance, and the act of swallowing can sometimes interrupt the Migrating Motor Complex cycle. Eating a small, easily digestible snack, such as a few crackers or a piece of fruit, will give the stomach contents to work on, which immediately helps to muffle the sounds.
To help prevent excessive noise throughout the day, focus on reducing the amount of air you swallow. Actions like chewing food thoroughly, avoiding talking while eating, and limiting carbonated beverages or chewing gum can significantly reduce gas accumulation. Maintaining a consistent pattern of smaller, regular meals throughout the day can also prevent the stomach from becoming completely empty, limiting the intensity of loud MMC-driven contractions.
While stomach growling is normal, seek medical advice if loud stomach noises are persistent and occur alongside other symptoms, which may indicate an underlying issue like a food intolerance, infection, or bowel obstruction. Symptoms requiring evaluation include:
- Severe or persistent abdominal pain.
- Unexplained weight loss.
- Chronic diarrhea or constipation.
- Nausea.
- Vomiting.
- Inability to pass gas.