The committee identified several other nutrition-related health risks and outcomes in its review of epidemiological evidence.
Vitamin D and Bone Health—Recent evidence suggests that vitamin D deficiency may be re-emerging as a health concern, especially for population subgroups in regions with seasonal variation in exposure to sunlight (Kreiter et al., 2000). Despite some controversy about the actual prevalence and public health significance of vitamin D deficiency,4 a calcium- and vitamin D-rich diet is important during periods of peak bone mass accretion (Raisz, 1999; Curran and Barness, 2000; Branca and Vatueña, 2001; New, 2001; Calvo and Whiting, 2003). The Dietary Guidelines note the importance of dietary sources of vitamin D for the elderly, persons with dark skin, and those with insufficient exposure to ultraviolet B radiation (DHHS/USDA, 2005). Recommendations from the American Academy of Pediatrics note the importance of vitamin D supplementation of breast-fed infants (AAP, 2005).
Zinc and Breast-Fed Infants 6 Through 11 Months—Chemical analyses of breast milk at various stages of lactation indicate that at 6 through 11 months postpartum, the zinc (and iron) content of breast milk alone is not sufficient for older infants (Krebs, 2000; Dewey, 2001; Krebs and Westcott, 2002). Thus, the content and bioavailability of zinc (and iron) in complementary foods become very important for fully breast-fed infants.
Calcium Intake and Lead Exposure—Studies of calcium intakes and exposure to lead suggest that adequate calcium intake has an added benefit of decreasing blood lead levels in pregnant women and lactating women (Hertz-Picciotto et al., 2000; Hernandez-Avila et al., 2003).
Dioxins—Dioxins are low-level environmental contaminants, but their presence in animal feed, food and water resources for animals in the wild (e.g., fish), and the human food supply is widespread. Because dioxins have a variety of potential toxic effects, including developmental effects on
There is recent evidence that vitamin D intakes are inadequate for adolescent and adult women of reproductive age (Moore et al., 2004). However, vitamin D intakes appeared adequate for children ages 1 to 8 years (Moore et al., 2004), indicating that vitamin D intakes are likely to be adequate among children in these age groups on a population basis. Nevertheless, vitamin D deficiency has been reported in population subgroups or the whole population in regions with seasonal variation in exposure to sunlight (Daaboul et al., 1997; Lawson and Thomas, 1999; Lawson et al., 1999; Kreiter et al., 2000; Dawodu et al., 2003). Thus, whether inadequate intakes of vitamin D are a public health concern remains controversial.