address appropriate uses of the DRIs for planning diets of groups and individuals.
In 1941, the Food and Nutrition Board first proposed the Recommended Dietary Allowance (RDA) for the U.S. population “to serve as a goal for good nutrition and as a ‘yardstick’ by which to measure progress toward that goal...” (NRC, 1941, p. 1). Even today, the many specific uses and applications of dietary reference standards fall into the two general categories defined implicitly in 1941: diet assessment and planning. Diet assessment applications involve determining the probable adequacy or inadequacy of observed intakes (a yardstick by which to measure progress). Diet planning applications involve using dietary reference standards to develop recommendations for what food intakes should be (as a goal for good nutrition). Obviously, these two general applications are interrelated.
The first dietary standards in Canada were issued by the Canadian Council on Nutrition in 1938. At the time it was stated that the standards were to be used as the basis for evaluating observed diets. In 1942, rather than revise the 1938 standards, the Canadian Council on Nutrition recommended that the 1941 RDAs be applied in Canada. However, by 1945 differences in the approach of the Canadian Daily Recommended Nutrient Intakes (DRNIs) and U.S. standards had become evident. The differences were conceptual and related to the application of the standards to individuals versus application to groups.
The most recent versions of the Canadian (now shortened to Recommended Nutrient Intakes [RNIs]) (Health and Welfare Canada, 1990) and U.S. (NRC, 1989) standards did not differ in the described derivations of the recommended intakes but some differences remained in how intended uses were described.
The new Dietary Reference Intakes (DRIs) differ from the former Recommended Dietary Allowances (RDAs) and Recommended Nutrient Intakes (RNIs) conceptually. These differences are that: (1) where specific data on safety and efficacy exist, reduction in the risk of chronic degenerative disease is included in the formulation of the recommendation rather than just the absence of signs of deficiency; (2) upper levels of intake are established where data exist regarding risk of adverse health effects; and (3) components