of food components for which RDAs and AIs may not be determined, and of the potential enhancement of nutrient utilization through interactions with other nutrients simultaneously. It is recognized, however, that the low energy intakes reported in recent national surveys may mean that it would be unusual to see changes in food habits to the extent necessary to maintain intakes by all individuals at levels recommended in this report. Eating fortified food products represents one method by which individuals can increase or maintain intakes without major changes in food habits. For some individuals at higher risk, use of nutrient supplements may be desirable in order to meet recommended intakes.
It is not the function of this report, given the scope of work (see Appendix A, Origin and Framework of the Development of Dietary Reference Intakes), to address in detail applications of the DRIs, including considerations necessary for the assessment of adequacy of intakes of various population groups and for planning for intakes of populations or for groups with special needs. However, some uses for the different types of DRIs are described briefly in Chapter 9. A subsequent report is expected to focus on the uses of DRIs in various settings.
Table S-1, Table S-2, Table S-3, Table S-4 through Table S-5 present the criteria used for deriving the age-group specific EARs and AIs, as well as the values for EARs, AIs, and RDAs. For vitamin D, the same criterion was used for all the life stage groups; however, for calcium, phosphorus, and magnesium, different criteria were used for some of the life stage groups. For calcium for those ages one year and older, three lines of evidence were considered as described previously, yet due to a lack of experimental evidence for ages 1 through 3 and greater than 70 years, estimates of the AI were extrapolated from other age groups.
The DRIs presented in these tables do not differ by gender except for magnesium and fluoride (because of the gender difference in average body weight). For the other nutrients, differences by gender were not apparent. For calcium, vitamin D, and fluoride, AIs have been estimated. For calcium, phosphorus, vitamin D, and fluoride, the evidence indicated that the AIs or EARs for pregnant and lactating women were no different from those for adolescents and adults of the same age. For magnesium, there was a slight increase in the EARs during pregnancy, but not during lactation.
It is important to recognize that the major focus in the develop-