Intestinal gurgling, medically termed borborygmi, is the common sound of a functioning digestive tract. These rumbling, bubbling, or growling noises are generally a normal sign that the gastrointestinal system is active. The sounds are created by the movement of liquid, gas, and partially digested food through the stomach and intestines.
The Physiology Behind the Noise
The characteristic gurgling sounds are a direct result of peristalsis, the wave-like contraction and relaxation of the smooth muscles lining the digestive tract. This muscular action pushes the contents—a mixture of solids, fluids, and gas—forward through the intestines. As these components are propelled through the narrow passageways, the mixing and movement of air bubbles within the liquid create the audible rumbling.
These movements occur constantly, even when the stomach is empty. When the digestive tract is full of food, the sounds are muffled because the contents absorb the vibrations. When the intestines are empty, there is less material to absorb the sound, making the gurgling louder and more noticeable.
Common Causes of Intestinal Gurgling
The most recognized cause of loud gurgling is hunger, linked to the migrating motor complex (MMC). The MMC is a cyclical pattern of strong muscle contractions that sweeps through the stomach and small intestine during fasting. This “housekeeping” function clears out residual debris and prepares the gut for the next meal. The rumbling noise is the sound of these powerful waves moving through an empty space.
Gurgling also occurs as a normal part of active digestion after eating. The movement of gas plays a significant role in creating these noises, generated primarily through two means. The first is swallowing air (aerophagia), which happens when an individual eats or drinks too quickly, chews gum, or drinks carbonated beverages. The second source is the fermentation of undigested carbohydrates by gut bacteria, which produces gas that moves through the intestines.
When Gurgling May Indicate a Health Issue
While most gurgling is normal, hyperactive (louder, more frequent) or hypoactive (quieter, less frequent) sounds, especially when accompanied by other symptoms, can signal an underlying health issue. Gastrointestinal disorders like Irritable Bowel Syndrome (IBS) frequently cause excessive abdominal noise, often alongside chronic abdominal pain, bloating, and alternating diarrhea or constipation. Small intestinal bacterial overgrowth (SIBO) can also lead to increased noise and discomfort, as displaced bacteria ferment food and produce large amounts of gas.
Food intolerances or allergies represent another common cause of excessive borborygmi, as the incomplete digestion of certain components leads to fermentation and gas production. For example, lactose intolerance results from a lack of the enzyme lactase, causing undigested lactose to ferment in the large intestine. Similarly, consuming foods with high amounts of fermentable sugars and artificial sweeteners, such as fructose and sorbitol, can increase gas and gut noise.
A sudden increase in gurgling may also be a symptom of an acute infection, such as gastroenteritis or “stomach flu,” caused by viruses or bacteria like Salmonella or E. coli. In these cases, the hyperactive bowel sounds are usually accompanied by diarrhea, vomiting, or fever. However, the most concerning signs warranting immediate medical attention are the complete absence of bowel sounds, or conversely, very high-pitched, frequent sounds. These are especially concerning if coupled with severe, persistent abdominal pain, vomiting, or an inability to pass gas or stool, suggesting a serious complication like an intestinal obstruction or paralytic ileus.
Reducing Excessive Stomach Noise
For individuals bothered by the sounds of a healthy gut, several simple lifestyle adjustments can help minimize the noise. One effective strategy is to reduce the amount of air swallowed by eating more slowly and chewing food thoroughly. Avoiding behaviors like drinking through a straw, chewing gum, or talking excessively while eating can also prevent aerophagia.
Adjusting the diet to limit gas-producing foods is another practical step. This includes reducing the intake of fermentable foods like beans, lentils, and certain cruciferous vegetables, such as broccoli and cabbage. Staying hydrated by drinking water throughout the day helps ensure smooth movement of contents through the digestive tract. Finally, maintaining regular mealtimes helps prevent the prolonged fasting periods that trigger the loudest hunger gurgles.