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Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc
dietary data can be found in the report Dietary Reference Intakes: Applications in Dietary Assessment (IOM, 2000).
Using the Recommended Dietary Allowance for Groups
The Recommended Dietary Allowances (RDAs) are not useful in estimating the prevalence of inadequate intakes for groups. As described above, the EAR should be used for this purpose.
Using the Adequate Intake for Groups
In this report, Adequate Intakes (AIs) are assigned for infants, and they reflect the average intake for infants receiving human milk through 6 or 12 months of age. Human milk and formulas with the same nutrient composition as human milk (after adjustment for bioavailability) provide the appropriate levels of nutrients for full-term infants of healthy, well-nourished mothers. Groups of infants consuming formulas with lower levels of nutrients than human milk may be at some risk of inadequacy, but the prevalence of inadequacy cannot be quantified.
AIs are assigned to all age groups in this report for vitamin K, chromium, and manganese. For vitamin K and manganese, AIs were based on median intakes of apparently healthy populations as assessed in large national surveys. By definition, this means that groups with median intakes equal to or above the AI can be assumed to have a low prevalence of inadequacy (provided that variability in intake does not exceed that of the healthy group used to establish the AI). However, it should be noted that group median intakes below the AI cannot be assumed to be inadequate. For chromium, the AI was established by using an estimated amount of chromium/1,000 kcal of nutritionally balanced meals and median energy intakes from NHANES III (Briefel et al., 1997). Thus, there is less certainty about concluding that the prevalence of nutrient inadequacy is low in groups with mean usual intakes equal to or above the AI for chromium.
Using the Tolerable Upper Intake Level for Groups
The proportion of the population with usual intakes below the Tolerable Upper Intake Level (UL) is likely to be at no risk of adverse effects due to overconsumption, but the proportion above the UL may be at some risk. In the case of zinc, for example, the UL for adults is 40 mg/day. The NHANES III data in Appendix Table C-26,