Thought I'd share some interesting info I came across regarding flatulence. It's from Myths and Realities Concerning Digestion at www.diagnosishealth.com/myths.htm It does seem to address some of the questions I see come up on this board.MYTH: The gas I pass comes from swallowed air..."Only a small component of gas passed as flatus is derived from swallowed air. Most of the air we swallow is actually absorbed across the bowel wall into the bloodstream. Very little reaches the rectum. Most flatus is the result of breaking down of unabsorbed carbohydrates."MYTH: Flatus is the same among different people..."While the basic gases are the same...approximately one-third of the world's population has methane-producing bacteria that lead to production of methane gas."MYTH: Floating stool is a sign of indigestion and malabsorption..."Until the not-too-distant past it was thought that floating stools imply fat in the stool as a result of fat malabsorption. This is not entirely true A much-more-common cause is air trapped in the stool."MYTH: A bowl movement during or soon after a meal means ingested food is coming out without digestion...."The digestive tract is very long and it would be highly unusual for food to traverse the entire food pipe during or soon after eating. What happens is that the somach and colon are connected by nerve-reflexes. The richer the food, the more the stimulation of the colon. This stimulated colon starts to act up, shaking things up inside, and the result is a bowel movement."MYTH: Chronic conditions of the digestive system start at a young age...."Chronic digestive ailments typically appear in middle age and continue or worsen with aging. Part of the reason is that various systemic conditions become more common with age."MYTH: Output of loose stools excludes constipation...."Sometimes stools are so backed up in the colon that a part of the hardened stool blocking the pasage opens up and liquid stool may squirt around this compaction."And last but not least:MYTH: Reports of explosions occurring in the bowel are false..."Explosions have occurred in the bowel during procedures where electric cautery is applied. When stool is present in the colon, there is fermentaiton of unabsorbed carbohydrates by the bacteria. Many of the gases produced as a result of this breaking-down process are combustible. Exposure to electric current may result in explosion in the colon (just like a bomb, literally) and such cases have been reported in scientific literature. Therefore, during lower GI scope (colonoscopy) we do not use electric current if the colon has not undergone adequate cleansing."