Dietary fiber: analysis and food sources.

The sources of dietary fiber are reviewed and the chemistry of the various components discussed in relation to their possible physiological properties and their analytical measurement in foods and the diet as a whole. Complete fractionation of all the polysaccharide species would be a time-consuming exercise; nevertheless some characterization of dietary fiber seems essential to an understanding of any physiological role. The composition of the dietary fiber in a range of foodstuffs is presented, and the relative contributions of the major food groups to the intake of total dietary fiber is outlined.