The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 537...
... 3. In determining the reference values for vitamin D, confounding factors are important considerations, notably those that affect the DRI population groups such as latitude, sun exposure, skin pigmentation, vi 1Estimated Average Requirement: The average daily nutrient intake level that is estimated to meet the requirements of half of the healthy individuals in a particular life stage and gender group (Dietary Reference Intakes: The Essential Guide to Nutrient Requirements, IOM 
From page 538...
... For vitamin D, the target population may also include subgroups within the general population whose requirements for vitamin D intakes may need to be considered within the context of limited endogenous synthesis or differences in metabolic handling of vitamin D (e.g., limited sun exposure because of latitude, clothing, institutionalization, dark skin pigmentation; older persons with reduced capacity for dermal synthesis; racial/ethnic differences in metabolic handling of these nutrients)
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More information on Chapter Skim is available.