The Dietary Reference Intake (DRI) is a system of nutrition recommendations from the Institute of Medicine (IOM) of the U.S. National Academy of Sciences. The DRI system is used by both the United States and Canada and is intended for the general public and health professionals. Applications include:
Composition of diets for schools, prisons, hospitals or nursing homes.
Industries developing new food stuffs.
Healthcare policy makers and public health officials.The DRI was introduced in 1997 in order to broaden the existing guidelines known as Recommended Dietary Allowances (RDAs). The DRI values are not currently used in nutrition labeling, where the older Reference Daily Intakes are still used.
The Recommended Dietary Allowance (RDA) was developed during World War II by Lydia J. Roberts, Hazel Stiebeling, and Helen S. Mitchell, all part of a committee established by the United States National Academy of Sciences in order to investigate issues of nutrition that might "affect national defense".
The committee was renamed the Food and Nutrition Board in 1941, after which they began to deliberate on a set of recommendations of a standard daily allowance for each type of nutrient. The standards would be used for nutrition recommendations for the armed forces, for civilians, and for overseas population who might need food relief. Roberts, Stiebeling, and Mitchell surveyed all available data, created a tentative set of allowances for "energy and eight nutrients", and submitted them to experts for review.
The final set of guidelines, called RDAs for Recommended Dietary Allowances, were accepted in 1941. The allowances were meant to provide superior nutrition for civilians and military personnel, so they included a "margin of safety." Because of food rationing during the war, the food guides created by government agencies to direct citizens' nutritional intake also took food availability into account.
The Food and Nutrition Board subsequently revised the RDAs every five to ten years. In the early 1950s, United States Department of Agriculture nutritionists made a new set of guidelines that also included the number of servings of each food group in order to make it easier for people to receive their RDAs of each nutrient.
The current Dietary Reference Intake recommendation is composed of:
Estimated Average Requirements (EAR), expected to satisfy the needs of 50% of the people in that age group based on a review of the scientific literature.
Recommended Dietary Allowances (RDA), the daily dietary intake level of a nutrient considered sufficient by the Food and Nutrition Board to meet the requirements of 97.5% of healthy individuals in each life-stage and sex group. It is calculated based on the EAR and is usually approximately 20% higher than the EAR.
Adequate Intake (AI), where no RDA has been established, but the amount established is somewhat less firmly believed to be adequate for everyone in the demographic group.
Tolerable upper intake levels (UL), to caution against excessive intake of nutrients (like vitamin A) that can be harmful in large amounts. This is the highest level of daily consumption that current data have shown to cause no side effects in humans when used indefinitely without medical supervision.
The RDA is used to determine the Recommended Daily Value (RDV) which is printed on food labels in the U.S. and Canada.
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