Folate intake and blood concentrations of term infants.

Folate nutrition of 67 full-term infants was studied longitudinally from birth to 1 year. Infants were grouped according to type of milk consumed during early infancy: group I (n = 14) received human milk; group II (n = 31), a standard cow-milk infant formula; and group III (n = 22), the same formula with added iron (12.3 mg/L). Solid foods were introduced after 3 months. Folate status, as indicated by serum and red blood cell folate concentrations, and folate intake were measured periodically. Blood folate concentrations of all groups were higher than or similar to adult control values. No differences in indices of folate status were observed between formula-fed groups at any time frame. At 6 weeks and 3 months formula-fed infants had folate intakes and blood concentrations significantly greater than human milk-fed infants. With the introduction of solid foods, decreases in blood folate concentrations paralleled decreases in milk folate intake within each group. Serum folate concentrations correlated with both total folate intake and milk folate intake, whereas RBC folate concentrations correlated with only milk folate intake. The results indicate that milk, regardless of type (human milk, formula, and cow milk), is an important dietary source of folate during the first year of life and that both human milk and proprietary formula feeding during early infancy provide more than sufficient folate to maintain blood folate concentrations well above acceptable limits.