Fibre, fermentation, flora, and flatus

Abstract

Research into flatogenesis has undergone several, apparently unrelated, phases. Early studies of the volume of gas in the gastrointestinal tract were prompted by the abdominal pain and discomfort experienced by sailors and airmen who had been subjected to explosive decompression. The second phase was aided by the realisation that human gas production could pose an explosion hazard during longterm space flight. Since that time, there has been little attempt to quantitate gas production in man although there have been many studies on concentrations of H2 and CH4 in end expired breath. There have been remarkable advances during the last 15 years in our understanding of the nature of non-absorbed sugars and dietary fibre and of their fermentation in the large intestine. It is now possible to construct a clearer picture of the overall stochiometry of colonic fermentation and gas production in man. In this study, an attempt has been made to determine the stochiometry of fermentation of defined substrates by incubation of faecal samples from a H2 and a CH4 producer. It addresses the essential questions of 'How much', 'Why?', 'Where?', 'What?', and 'Why not?'.