Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate (2005) / Chapter Skim
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1 Introduction to Dietary Reference Intakes
1 Introduction to Dietary Reference Intakes
Pages 21-36
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From page 21... ...
The development of DRIs expands on two series of reports, the Recommended Dietary Allowances, which have been published since 1941 by the National Academy of Sciences, and the Recommended Nutrient Intakes of Canada. This comprehensive effort is being undertaken by the Standing Committee on the Scientific Evaluation of Dietary Reference Intakes of the Food and Nutrition Board, Institute of Medicine of the National Academies, with the active involvement of Health Canada.
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From page 22... ...
Qualified medical and nutrition personnel must tailor recommendations for individuals who are known to have diseases that greatly increase nutritional requirements or who are at risk for developing adverse effects associated with higher intakes. Although the RDA or AI may serve as the basis for such guidance, qualified personnel should make necessary adaptations for specific situations CATEGORIES OF DIETARY REFERENCE INTAKES Each type of Dietary Reference Intake (DRI)
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From page 23... ...
Estimated Average Requirement The Estimated Average Requirement (EAR) is the daily intake value that is estimated to meet the requirement, as defined by the specified indicator or criterion of adequacy, of half of the apparently healthy individuals in a life stage or gender group (see Figure 1-1)
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The methods used for extrapolation are described in Chapter 2. Method for Setting the RDA When Nutrient Requirements Are Normally Distributed If the requirement for the nutrient is normally distributed, and the standard deviation (SD)
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For example, for basal losses of a nutrient, a distribution of expected losses can be generated. For each individual in the simulated population, a randomly selected basal loss value was drawn from that distribution of nutrient losses.
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From page 26... ...
For example, for young infants for whom human milk is the recommended sole source of food for almost all nutrients for the first 4 to 6 months, the AI is based on the daily mean nutrient intake supplied by human milk for healthy full-term infants who are exclusively fed human milk. For adults, the AI may be based on data from a single experiment, on esti
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From page 27... ...
Tolerable Upper Intake Level The Tolerable Upper Intake Level (UL) is the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects for almost all apparently healthy individuals in the specified life stage group (see Figure 1-1)
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From page 28... ...
For some nutrients, data are not sufficient for developing a UL for apparently healthy individuals. This indicates the need for caution in consuming amounts greater than the recommended intakes; it does not mean that high intakes pose no risk of adverse effects.
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From page 29... ...
During the second 6 months of life, growth velocity slows, and thus total daily nutrient needs on a body weight basis may be less than those during the first 6 months of life. For a particular nutrient, the average intake by full-term infants who are born to healthy, well-nourished mothers and exclusively fed human milk has been adopted as the primary basis for deriving the AI for nutrients during the first 6 months of life.
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From page 30... ...
Except for some nutrients such as iron and zinc, for which infants have relatively high requirements, there is no evidence for markedly different nutrient needs during the period of infants' slower growth and gradual weaning to a mixed diet of human milk and solid foods from ages 7 through 12 months. The basis of the AI values derived for this age category was the sum of the specific nutrient provided by 0.6 L/day of human milk, which is the average volume of milk reported from studies in this age category (Heinig et al., 1993)
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From page 31... ...
One problem that occurs in estimating intake data in infants is the lack of available data on total nutrient intake from a combination of human milk and solid foods in the second 6 months of life. Most intake survey data do not identify the milk source, but the published values for total intake indicate that cow milk or formula based on cow milk was most likely consumed along with weaning foods (Specker et al., 1997)
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From page 32... ...
All children continue to grow to some extent until as late as age 20 years; therefore, having these two age categories span the period 9 through 18 years of age seems justified. Young Adulthood and Middle Ages: Ages 19 Through 30 Years and 31 Through 50 Years The recognition of the possible value of higher nutrient intakes during early adulthood on achieving optimal genetic potential for peak bone mass was the reason for dividing adulthood into ages 19 through 30 years and 31 through 50 years.
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From page 33... ...
In some cases, where data regarding nutrient requirements are reported on a body-weight basis, it is necessary to have reference heights and weights to transform the data for comparison purposes. Frequently, where data regarding adult requirements represent the only available data (e.g., on adverse effects of chronic high intakes for establishing Tolerable Upper Intake Levels [ULs]
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From page 34... ...
Appendix B includes information about the reference values that were used in the earlier DRI reports. TABLE 1-1 Current Reference Heights and Weights for Children and Adults in the United States Median Body Median Reference Mass Indexa Weightb Reference (kg/m2)
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From page 35... ...
These reference values are being developed for specific life stage and gender groups in a joint U.S. and Canadian activity.
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From page 36... ...
2002/2005. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids.
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