The fundamental idea of eating for Irritable Bowel Syndrome is to avoid the IBS trigger foods that irritate a spastic colon via the gastrocolic reflex that occurs when food enters the stomach, and to eat the soluble fiber safe foods that soothe and regulate the colon. This will relieve and prevent BOTH constipation and diarrhea, as well as the painful spasms and cramps, gas, nausea, and bloating of Irritable Bowel Syndrome.

For more info: http://www.helpforibs.com/diet/trigger1.asp