the general population. The DRI reports, however, include separate life stage and gender groups for which reference values often differ. The most scientifically valid approach to combining these life stage and gender group values to obtain one number for nutrition labeling is to apply weighting based on population census data.

An important component of the DRI concept is how each reference value has been derived and the relevance of the derivation for different applications. For the purposes of nutrition labeling, the committee’s task was to provide guidance for the development of reference values that could be used by an individual to compare the nutrient content of food items within food types and to make purchase decisions in the context of the food’s contribution to his or her total daily diet. The best point of comparison for the nutrient contribution of a particular food is the individual’s nutrient requirement. It is almost impossible to know the true requirement of any one individual, but a reasonable estimate can be found in the median of the distribution of requirements, or the EAR. The EAR is a daily intake value defined by carefully selected measures of adequacy based on biochemical, functional, or other markers or indicators. As such, the EAR represents the best current scientific estimate of a reference value for nutrient intake based on experimental and clinical studies that have defined nutrient deficiency, health promotion, and disease prevention requirements. For those nutrients for which the distributions of nutrient requirements for particular life stage and gender groups have been characterized, then the best, most representative estimate of an individual’s requirement or need is the EAR for the group to which he or she belongs. A level of intake above or below the EAR will have a greater likelihood of systematically over- or underestimating an individual’s needs. The RDA is derived from the EAR and is defined to be 2 standard deviations above the EAR on the nutrient requirement distribution curve. Therefore the RDA is not the best estimate of an individual’s nutrient requirement. For these reasons the committee recommends the use of a population-weighted EAR as the basis for the DV when an EAR has been set for a nutrient. This approach should provide the most accurate reference value for the majority of the population.

EARs have not been set for some nutrients included in nutrition labeling. For these nutrients the committee recommends using a population-weighted AI as the reference value for the DV. AIs were set for nutrients only when there was insufficient scientific evidence to calculate an EAR. AIs were derived using a diversity of methods based on the best scientific information available. As a result, until more research is completed that allows calculation of the mean and



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