the fractional zinc absorption, it is assumed that the older infant continues to be fed human milk between 7 and 12 months of age along with complementary foods. The fractional absorption of zinc from human milk continues to approximate 0.5 (Abrams et al., 1997). Based on an average intake of 500 μg/day from human milk and a fractional absorption of 0.5, the amount of zinc ingested from milk is approximately 250 μg/day. Therefore the estimated absorbed zinc required from complementary foods is 586 μg/day (836–250). Applying a fractional absorption of 0.3, zinc intake required from complementary foods is 1.95 mg/day (586 ÷ 0.3). Therefore, the EAR for infants ages 7 through 12 months is 2.5 mg/day (0.5 + 1.95). For children ages 1 through 3 years, a fractional absorption of 0.3 is used to estimate the required dietary zinc resulting in an EAR of 2.5 mg/day (744 ÷ 0.3), after rounding.

Extrapolation from Adults. An average requirement of 2.3 and 3.0 mg/day for older infants and young children, respectively, is calculated with use of the method described in Chapter 2 that extrapolates from the adult EAR based on body size.

Growth. Limited dietary zinc data are available for children in this age group. In a 6-month, placebo-controlled, randomized zinc supplementation study (Walravens et al., 1989), a major criterion for