This is part FACT, part MYTH.
Your stomach growls when you’re hungry and when you’re full, but it growls the loudest when it’s empty, which is why a rumbling tummy is typically linked to hunger. The growling might not be coming from your stomach at all, but from your small intestines, and it may be churning away with grumbles without you even hearing it. Let’s take a look at the precise mechanism behind a growling stomach.
Why Your Stomach Growls
Growling is caused when your intestinal wall contracts in the presence of liquid and gas, which happens pretty much throughout the day and calms during sleep. When you hear your stomach growl it is most likely engaging in a process called migrating motor complex (MMC), which kicks in when your stomach and intestines have been empty of food for about two hours.
Your stomach wall is lined with receptors that can tell when there is no food present. During MMC, these receptors send waves of electrical activity to the enteric nervous system of your gut, which acts like your second brain. Your enteric nervous system responds by triggering hunger contractions that work to remove stomach debris, food particles, mucus, and bacteria from your gut. If your body’s MMC isn’t properly working, then you may be suffering from abdominal distress, vomiting, nausea, or indigestion.
Should I Be Concerned?
A growling stomach is nothing to be worried about, but if you are experiencing more frequent and louder bowel sounds than normal, your gut may be signaling some type of digestive trouble, including illnesses such as dyspepsia, irritable bowel syndrome, diarrhea, celiac disease, or lactose intolerance.
Sugar can also cause a stomach to growl more loudly. Cut down on the sugar and eat probiotic-rich foods such as fermented vegetables, which help cultivate healthy bacteria in your gut and keep your stomach growling at normal decibels.