[Dietary fiber in internal medicine]

The suggestion that dietary fibre is of particular importance in our diet is a relatively recent concept. Much of the initial emphasis for increased dietary fibre began with the pioneering work of Burkitt and Trowell in the 1960s who observed that traditional African populations consumed diets high in plant fibre and that these populations experienced very low incidences of non-communicable diseases including cardio-vascular disease, diabetes mellitus and non-infectious bowel diseases, including cancer. Although it is difficult to predict from the chemical structure how dietary fibres will behave physiologically, generally dietary fibre sources can be grouped into two major types: (a) soluble, viscous, fermentable and (b) insoluble, non-viscous, slowly fermentable. As detailed below, these sources of fibres appear to have quite different physiological effects.