What is Irritable Bowel Syndrome?
It is a commonly found disorder of the digestive system. It is a group of symptoms representing functional disorder, not a disease. IBS is not considered dangerous for health in the sense that it does not cause other serious health problems but is quite bothersome and annoying. The condition may be acute or chronic, may change from time to time or may even disappear for some time.

Causes
Modern medical science is unaware of the exact cause of IBS. Why the cramping of abdomen occurs is not known. If you ask for the cause, you would usually be given the explanation of how the intestines act, how the food is digested and moved through the system and that in case of IBS your system is not working correctly but why that happens has no explanation. Basically it is only a dysfunction of the nervous system that controls the process of digestion. It occurs due to frequent and prolonged use of certain food items that vary from person to person and affect according to sensitivity of the person.

IBS is not difficult to cure. All that it takes is few homeopathic medicines and initially some changes in the diet according to symptoms.
Once patient's immunity is strong enough, they can eat anything they like, of course in sensible amounts.