At the present time, the exact cause of Irritable Bowel Syndrome (IBS) is not known.
The walls of the intestines in the digestive tract are lined with layers of muscle that contract and relax as they shift food from your stomach through your intestinal tract towards your rectum. Normally, these muscles contract and relax in a synchronized rhythm, called peristalsis, and food is pushed through the intestine at the proper speed for processing.
Peristalsis Gone Bad
However, in those with Irritable Bowel Syndrome (IBS) these contractions can be stronger and last longer than normal, forcing food through the intestines faster, and this can cause gas, bloating, and diarrhea.
At other times, the opposite may occur, and food is moved through the intestines at a slower pace, causing stools to become hard and dry, leading to constipation.
Some researchers believe that IBS may be caused by changes in the nerves that control muscle contractions in the bowel.
Others think that hormonal changes may play a role in bringing about irritable bowel syndrome, especially in Women. This possibility is strengthened by the fact that many women experience more severe IBS symptoms during their menstrual periods.
Recently, research has found that serotonin is linked with normal gastrointestinal functioning. Serotonin is a neurotransmitter which that delivers messages from one part of your body to another.
95% of the serotonin in your body is located in the gastrointestinal tract, and the other 5% is found in the brain. In has been found that the cells that line the inside of the bowel work as transporters and carry the serotonin out of the gastrointestinal tract.
People with IBS, however, seem to have reduced receptor activity, causing abnormal levels of serotonin to exist in the gastrointestinal tract. As a result, people with IBS experience problems with bowel movement, motility, and sensation as a result of having more sensitive and active pain receptors in their gastrointestinal tract.
Further research is required into the causes of Irritable Bowel Syndrome.