include appropriate standards to use in determining whether diets are nutritionally adequate without being excessive. The DRIs encompass more aspects of nutrition than did the earlier RDAs, as follows:
DRIs consider reduction in the risk of chronic disease, as well as the absence of signs of deficiency.
For most nutrients, DRIs include both RDA and Estimated Average Requirement (EAR) values.
For some nutrients, insufficient data were available to set EAR and RDA values. For these nutrients, Adequate Intake (AI) values were estimated.
DRIs include Tolerable Upper Intake Levels (ULs), which are used in the evaluation of the risk of adverse effects from excess consumption.
DRIs specify appropriate ranges of macronutrient densities, which are called Acceptable Macronutrient Distribution Ranges (AMDRs).
When adequate data are available, DRIs provide reference values for food components other than nutrients.
At the time the WIC program was established, there was no systematic process for the development and revision of science-based dietary guidance for the U.S. population. However, guidance on food intakes is available now. Nutrition education tools such as the Four Food Groups focused on eating enough of various types of foods to ensure nutrient adequacy. The original selection of foods for the WIC food packages was based on food consumption data that indicated that calcium, iron, vitamin A, and vitamin C were the nutrients most likely to be low in the diets of low-income women and young children. Understanding of the necessity for adequate high-quality protein in periods of rapid growth and development provided the basis for inclusion of protein as a target nutrient. The specific foods selected for the food packages are good sources of the nutrients listed above, as well as widely available, generally acceptable, and reasonable in cost.
As deficiency diseases became less common, scientific research into the relationships between various dietary components and chronic diseases expanded. In 1977, the U.S. Senate Select Committee on Nutrition and Human Needs published Dietary Goals for the United States (U.S. Senate, 1977). This was the first government publication that set forth dietary guidance that included a focus on the total diet and recommendations both for minimizing risk of chronic disease and for ensuring nutritional adequacy. Much controversy surrounded these goals because of the lack of agreement among scientists on many of the issues and because of the pro-