ST. PAUL, Minn.--The American Association of Cereal Chemists (AACC) on June 1 approved a new definition of dietary fiber. It is the first revision of the definition in more than 25 years, when it was developed by researcher H. Trowell and his associates.

AACC instituted an ad hoc committee in late 1998, and after a consensus was reached, its board of directors approved the final definition. As approved, it reads: Dietary fiber is the edible parts of plants of analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine. Dietary fiber includes polysaccharides, oligosaccharides, lignin, and associated plant substances. Dietary fibers promote beneficial physiological effects including laxation, and/or blood cholesterol attenuation, and/or blood glucose attenuation."