More people are becoming aware of the new Dietary Reference Intakes (DRI) that have been released by the Food and Nutrition Board of the National Academy of Science.

The Dietary Reference Intakes refer to four nutrient reference values that can be used to assess diet, as well as for other purposes. The DRIs are a replacement for the well-known RDAs (Recommended Dietary Allowances) of the United States, which have been published since 1941 by the National Academy of Sciences, and the RNIs (Recommended Nutrient Intakes) of Canada . These new values are the collaborative work of the Standing Committee on the Scientific Evaluation of Dietary Reference Intakes of the Food and Nutrition Board, the Institute of Medicine, the National Academy of Sciences, and Health Canada.

Unlike the RDAs, which establish the minimal amounts of nutrients required to protect against possible deficiencies, the new DRIs are designed to reflect a more modern understanding of nutrient requirements, to optimize health in people and groups of people.

The DRIs are comprised of four reference values. These include the RDA and three other values:

• Recommended Daily Allowance (RDA): The average daily dietary intake level that is sufficient to meet the nutrient requirement of nearly all (97 to 98 percent) healthy individuals in a group. In other words, the RDA is the amount of vitamins and minerals that a healthy person requires to stay healthy. These amounts will prevent obvious vitamin deficiencies, such as scurvy and rickets. However, these values are really quite conservative, and most nutritionally trained doctors like ourselves feel that they are generally too low for optimal health.

• Adequate Intake (AI): A value based on observed or experimentally determined approximations of nutrient intake by a group (or groups) of healthy people. Used when an RDA cannot be determined.

• Tolerable Upper Intake Level (UL): The highest level of daily nutrient intake that is likely to pose no risk of adverse health effects to almost all individuals in the general population. As intake increases above UL, the risk of adverse effects increases.

• Estimated Average Requirement (EAR): A nutrient intake value that is estimated to meet the requirement of half the healthy individuals in a group.

• Note: In our discussion of each vitamin and mineral we have included our own adult Optimal Intake reference ranges. The Optimal Intake references are our estimates of the dosages of vitamins and minerals that provide the best chance of bringing about optimal health and not just the prevention of disease.