Our gut is a long muscular tube that churns, digests and propels the food through the alimentary canal. Nutrients from the food are extracted and absorbed by the cells that line the intestines. All this activity in the bowel produces various types of sounds, most of which remain unnoticed. Sometimes, low-pitched grumbling noises can be heard, which are technically known as borborygmi (singular ~ borborygmus).
The bowels may also produce louder sounds that are clearly audible. This happens with strong contractions and gas in the bowels. However, this are occasional rather than continuous occurrences. If loud sounds from the bowel occur in a persistent manner, a hyperactive bowel is usually the cause. Hyperactivity of the bowels occurs for many reasons.
Read more on stomach noises.
Reasons for Bowel Sounds
Bowel sounds are usually described by using different terms such as rumbling, growling, roaring, or bubbling. The description depends on the characteristics of the sound produced. These diverse sounds are produced by the following mechanisms:
- Movement of food: Our gut wall is lined by layers of smooth muscles. Strong contractions of these muscles help break down the food and propel the waste towards the end of the colon. The contractions of these muscles squeeze and push the food through the gut, enabling the different processes of digestion, water and nutrient absorption, and waste formation. These movements contribute to the normal bowel sounds.
- Movement of water: A large quantity of water is secreted into the upper part of the bowel by the cells lining it. This helps in the movement and digestion of food in this part of the intestine. However, most of the water is absorbed back in the lower region (colon) of the intestine. The movement of water in the bowels also contributes to the sounds produced in this region of the alimentary canal.
- Movement of gas: Movement of gas in the intestine also causes characteristic sounds. Gas in the upper part of the gut mainly comes from swallowed air and carbonated beverages. This gas is expelled through belching, and most of it does not reach the lower bowels. Gas is also produced in the lower part of the intestine through the process of digestion carried out by enzymes and bacteria in the gut. This gas is expelled as flatus. The gas can also cause noises as it bubbles in the fluid within the bowels.
The food material that enters the colon from the last part of the small intestine (the ileum) has the consistency of a fluid. By the time it reaches the end of the colon, most of the water has been reabsorbed and the food waste is turned into solid yet soft feces. Therefore bubbling sounds arising from the bowels is a normal phenomenon. These sounds are usually short-lived, and barely audible. However, bubbling sounds may become loud due to the following reasons:
- strong muscular contractions of the colon,
- food material in the colon is more fluid than is normal, and
- excessive amount of gas in the bowels.
Bubbling sounds may also emanate from the stomach and the upper gut. Often this bubbling does not occur in isolation and other symptoms may be present.
Bubbling sounds from the bowels may occur on its own or be accompanied by other symptoms such as:
- Bloating sensation
- Abdominal distension
- Excessive belching and flatulence
Read more on bubbling diarrhea.
Causes of Bubbling Sounds in the Bowels
There are multiple causes of bubbling sounds in the bowels. They range from acute conditions to chronic disorders. Following are the most common factors associated with bubbling sounds in the bowels:
- Diarrhea: Diarrhea is most commonly associated with bubbling sounds in the bowels. It is also characterized by increased water content and hyperactivity of the bowels which results in frequent bowel movements and loose stools. Diarrhea is a symptom that may occur in many different conditions. The bubbling sounds usually cease when the diarrhea stops.
- Irritable bowel syndrome (IBS): Irritable bowel syndrome is a chronic condition that is characterized by abnormally slow or abnormally fast bowel movements. The rapid motility and strong contractions associated with diarrheal IBS reduce the transit time of food through the colon. It may be associated with strong bowel muscle contractions, increased water content in the gut and possibly increased intestinal gas.
- Inflammatory bowel disease (IBD): Inflammatory bowel disease is also a chronic condition of the gut. Even the upper regions of the gut may get affected (as in Crohn’s disease). IBD is characterized by large quantity of water in the bowels, and a reduction in nutrient absorption. Watery, mucoid, or bloody diarrhea is associated with this condition.
- Food-related bowel disorders: Bubbling sounds in the bowels may also result from disturbances in the gut caused by specific foods. This includes conditions such as food allergies, food intolerance, and malabsorption of certain nutrients. Celiac disease, lactose intolerance and fructose malabsorption are a few examples of these types of disorders.
- Infectious bowel conditions: Bacterial infections are one of the most common reasons for diarrhea and bubbling sounds in the abdomen. Examples of infectious bowel diseases include gastroenteritis, enteritis and colitis. These diseases affect different parts of the gut. Gastroenteritis affects the stomach and the small intestine, enteritis affects the small intestine, and colitis affects the large intestine (colon).
- Food poisoning: Various toxins produced by pathogenic microorganisms are capable of causing irritation and inflammation of bowels. Some of these are ingested directly with contaminated food and water. Others are produced in the gut by the pathogenic microbes that enter the gut through contaminated food, contaminated water and lack of personal hygiene.
- Substance abuse: Substance abuse with alcohol, caffeine, nicotine, narcotics, and even prescription drugs, can cause bubbling sounds in the bowels. This is a result of direct irritation and inflammation of the intestinal walls caused by these substances. Even when present in the bloodstream, these substances can affect the activity of the nerves and muscles of the gut.
- Toxins: Poisoning with certain toxins results in inflammation and damage to the walls of the gut. These toxins also have many other local and systemic affects. In most cases, vomiting and diarrhea may follow ingestion of toxins. This is the bowel’s attempt to get rid of the poisonous substances.