presented, ultimately leading to the new DRIs. In many ways, these efforts considerably advanced the approach used to develop nutrient reference values. At that time we recognized that after some experience had been gained using this new approach, it would be worthwhile to pause and examine not only our successes, but the ways in which the approach could be improved. We are now at that point.
Reference values known in the United States as Recommended Dietary Allowances (RDAs) and in Canada as Recommended Nutrient Intakes (RNIs) were used through the 1990s. They were established primarily to set nutrition and health policy. In 1994, in response to important changes in the nutrition field as well as the recognition that for many nutrients the single RDA or RNI values did not meet the expanding needs for nutrient reference values, the IOM began an initiative to develop a new, broader set of values known as the DRIs. The U.S. and Canadian governments supported this initiative.
More specifically, the DRIs as reference values now
include upper levels of intake, where appropriate;
incorporate chronic disease endpoints within the array of endpoints that may serve to establish adequate intake or upper intake levels;
include “non-classical” nutrients;
specifically highlight concepts of probability and risk for defining reference values; and
are associated with publications intended to guide users of DRIs.
The DRI component values are shown in Box 1-1. They are described and contained in six volumes published by the IOM between 1997 and 2005. To help users understand the DRIs, given the expansion of both the nutrient reference value approach and the types of reference values issued, two publications were created to provide general guidance for users, one focused on planning and the other on assessment. In 2006, the IOM issued Dietary Reference Intakes: The Essential Guide to Nutrient Requirements, which is available in English and French.
A planning committee was convened early this year to assist the IOM in formulating the content and format of the workshop and in identifying candidates to serve as speakers, discussants, and panel members. The committee specified background materials to help participants prepare for the