Recommended dietary allowances-facts and uncertainties

Abstract

For the purpose of evaluating diets of individuals and populations, the nutrient requirements were defined. Over the years, recommendations across several countries have evolved. In India the ICMR report has a single value for a particular population group while in other countries up to 4 values have been reported. Currently the commonly used definitions are for the average nutrient requirements, recommended nutrient intake or dietary allowances and the upper nutrient/tolerable upper limit. Using these requirement constructs, not only can the risk of inadequate intakes be calculated (using the probability approach) but the risk for excessive intakes that cross upper limit can also be determined. With the increase in consumption of packaged foods and fortification, there needs to be clarity on the upper limit of nutrients, particularly those that are stored in the body (e.g. iron), to prevent toxicity.Uncertainties regarding specific requirements and controversies still prevail. This is because the measurement of the daily requirement is very difficult when accurate measurements are to be made in controlled conditions or under various physiological states. These typically are measured as that intake which balances daily losses. Equally, robust nutrient intake data is also required to compute the risk of deficiency or excess.