Recommended dietary allowance Reference Nutrient Intake

Optimal dietary intake is difficult to determine. Dietary Reference Intakes (DRIs) in the US are reference values that are quantitative estimates of nutrient intakes to be used for planning and assessing diets for apparendy healthy people. DRIs are composed of reference values including Estimated Average Requirements (EARs), Recommended Dietary Allowances (RDAs), Adequate Intakes (AIs) and Tolerable Upper Intake Levels (ULs). Most nations have established the equivalent of the US DRIs. These are consensus and statistical values obtained from retrospective public health dietary studies, controlled experiments on metabolic wards, epidemiological surveys, isotopic tracer investigations, and extrapolation from animal models. 

The Food and Nutrition Board of the U.S. National Academy of Sciences has recently devised a new nomenclature for human nutrient needs [30]. Dietary Reference Intakes (DRI) refer to a set of four nutrient-based reference values, termed the estimated average requirement (EAR), the recommended dietary allowance (RDA), adequate intake (AI), and the tolerable upper intake level (UL). The EAR is defined in the same way as in the CEC and UK recommendations. The RDA is now somewhat more rigorously defined to be the EAR + 2 SD (standard deviations), i.e. equivalent to the RNI and PRI in the UK and CEC systems. 

To replace recommended dietary allowances, the Food and Nutrition Board created the dietary reference intakes made up of seven nutrient groups. 

Reference Intakes (DRIs). In the past, the recommended dietary allowances (RDAs), which are the levels of intake of essential nutrients that are considered to be adequate to meet the known nutritional needs of practically all healthy persons, were the primary reference value for vitamins and other nutrients. The DRIs also include other reference values, such as the estimated average requirement (EAR) and the adequate intake (AI). The RDA, EAR, and AI reference standards define nutritional intake adequacy. Since these recommendations are given for healthy populations in general and not for individuals, special problems, such as premature birth, inherited metabolic disorders, infections, chronic disease, and use of medications, are not covered by the requirements. Separate RDAs have been developed for pregnant and lactating women. Vitamin supplementation may be required by patients with special conditions and for those who do not consume an appropriate diet. 

Recommended dietary allowances (RDA) for vitamins are recommended intake of various vitamin to ensure the good health of a high proportion of the human population. The RDA values quoted below refer to the United States population (Whitney and Rolfes, 1996). Reference nutrient intake... 

Committees of experts organized by the Food and Nutrition Board of the National Academy of Sciences have compiled Dietary Reference Intakes (DRIs)—estimates of the amounts of nutrients required to prevent deficiencies and maintain optimal health. DRIs replace and expand on Recommended Dietary Allowances (RDAs), which have been published wih periodic revisions since 1941. Unlike the RDAs, the DRIs establish Lpper limits on the consumption of some nutrients, and incorporate the role of nutrients in lifelong health, going beyond deficiency diseases. Boh the DRIs and the RDAs refer to long-term average daily nutrient itakes, because it is not necessary to consume the full RDA every day. 

The Institute is also responsible for establishing dietary reference intakes —quantitative estimates of nutrient intakes to be used for planning and assessing diets for healthy people—which update and replace the recommended dietary allowances. 

If sufficient scientific evidence is not available to calculate an Estimated Average Requirement, a reference intake called an Adequate Intake (Al) is used instead of a Recommended Dietary Allowance. The Al is a value based on experimentally derived intake levels or approximations of observed mean nutrient intakes by a group (or groups) of healthy people. The Al for children and adults is expected to meet or exceed the amount needed to maintain a defined nutritional state or criterion of adequacy in essentially all members of a specific healthy population LA = linoleic acid LNA = n-linolenic acid DHA = docosahexaenoic acid EPA = eicosapentaenoic acid TRANS-EA = trans fatty acids SAT = saturated fatty acids MONOs = monounsaturated fatty acids. 

Dietary Reference Intakes (DRIs) are used quite a lot and refer to a set of four nutrient-based reference values that represent the approach to provide quantitative estimates of nutrient intakes. The DRIs replace and expand on the Recommended Dietary Allowances (RDAs) for the United States and the Recommended Nutrient Intakes (RNIs) for Canada. The DRIs consist of the RDAs, the Tolerable Upper Intake Level (UL), the Estimated Average Requirement (EAR), and the Adequate Intake (AI). Generally, each of these values represents average daily nutrient intake of individuals in the diet (Goldhaber, 2003 Murphy and Poos, 2002 Parr et ah, 2006 Trumbo et ah, 2001 Yates et ah, 1998). In addition, dietary intake data for minerals could be assessed within the context of the bioavailability and other factors affecting the utilization of elements by the human body, such as age, sex, and health aspects (Dokkum, 1995). 

The Recommended Dietary Allowance (RDA) is the average daily dietary intake that is sufficient to meet the nutrient requirement of 97.5% of individuals and is set at 20% above the EAR -1-2 CVs where the CV is 10%. During recent years, dietary reference intakes have been revised by the US Institute of Medicine. The recommended intakes of Mg are given in Table 3. It is not known whether decreased urinary Mg and increased maternal bone resorption provide sufficient amounts of Mg to meet increased needs during lactation. Thus, the French Society for Nutrition suggests adding 30 mg/day to intake for lactation. 

LRNI, Lower Reference Nutrient Intake RNI, Reference Nutrient Intake Al, Adequate Intake RDA, Recommended Dietary Allowance. Sources UK Department of Health (1991) Dietary Reference Values for Food Energy and Nutrients for the United Kingdom, Report on Health and Social Subjects No. 41. London HMSO. USA Food and Nutrition Board, Institute of Medicine (2000) Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium and Carotenoids. Washington, DC National Academy Press. WHO/FAO WHO/FAO (2002) Human Vitamin and Mineral Requirements. Report of a Joint FAO/WHO Expert Consultation, Bangkok, Thailand. Rome WHO/ FAO. 

Age group US-Canadian recommended dietary allowance FAO/WHO reference nutrient intake Bioavailability High Moderate Low... 

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