Dietary Fiber Definitions at Risk
D. T. Gordon. Professor Emeritus, North Dakota State University. Cereal Foods World 52(3):112-123.
Defining dietary fiber (DF) remains an interesting and controversial issue. An international DF definition is important for food labeling (e.g., claims) and harmonization of global trade. The AACC International in 19992000 organized national and international forums to debate and propose a definition for DF. The U.S. Institute of Medicine (IOM) proposed a definition for DF. Although the IOM definition was reviewed by the U.S. Food and Drug Administration (FDA), the FDA is not in the process of accepting a definition. Consequently, there is no legal definition for DF in the U.S. While the national debate to establish a new definition for DF continues, the current international debate to define DF presents some strong differences of opinion. The Codex Committee on Nutrition and Foods for Special Dietary Use on behalf of the Codex Alimentarius Commission, as far back as 1992, but especially in the past four years, received agreement among its delegates to advance a definition. However, in July 2006, during a Food and Agricultural Organization/World Health Organization Scientific Update on Carbohydrates, a group of 11 carbohydrate experts (GROUP), two of whom were identified as DF experts, proposed that DF should be defined as consisting of intrinsic plant cell wall polysaccharides, and that DF should only be associated with fruits, vegetables, and whole grains. Furthermore, the GROUP recommended the adoption of a method of analysis for nonstarch polysaccharides that would support their definition. They further recommended that the AOAC INTERNATIONAL methods should be discarded. This perspective compares the strengths, limitations, and implications of these two internationally proposed definitions.