From basic science to dietary guidance: Dietary fiber as an example

Although dietary fiber is a nonessential nutrient it has achieved the status of having nutrient intake values and dietary recommendations. How it achieved this may serve as a prototype for other nonessential functional food components. An important step was the development of a worldwide accepted definition and the analytical method consistent with that definition. A database of fiber values in foods facilitated important prospective cohort studies investigating the effect of fiber intake on decreased risk of key diseases. The strongest data relating dietary fiber to health involved its laxation effect, but due to high individual variability, laxation was not the endpoint upon which the intake value for fiber was established. Instead, the intake value for dietary fiber was based on decreased risk of coronary heart disease and calculated from three prospective cohort studies. Other physiological effects of fiber on health that are generally accepted are decreased risk of type2 diabetes and effect on weight maintenance. Since the 2009 final Codex definition for dietary fiber states that fibers that are extracted or synthesized (as opposed to endogenous to the food) need to prove a physiological benefit to health, there is strong interest in establishing health benefits for these functional fibers.