BACKGROUND:

In adults, RRR-alpha-tocopheryl acetate (natural vitamin E) has approximately twice the biological activity of all-rac-alpha-tocopherol (synthetic vitamin E). Similar studies have not been done in term infants.

OBJECTIVE:

We evaluated the vitamin E and antioxidant status of term infants fed formulas differing in the amount and form of vitamin E acetate.

DESIGN:

A controlled, blinded, multisite study was completed with 77 term infants randomly assigned to 1 of 3 different infant-formula groups. The HIGHNAT-E formula (n = 26) contained 20 IU RRR-alpha-tocopheryl acetate/L (14.5 mg/L), the LOWNAT-E formula (n = 25) contained 10 IU RRR-alpha-tocopheryl acetate/L (7.3 mg/L), and the SYN-E formula (n = 26) contained 13.5 IU synthetic all-rac-alpha-tocopheryl acetate/L (13.5 mg/L). A human milk-fed group (n = 29) served as a reference.

RESULTS:

Although the LOWNAT-E formula contained only one-half the concentration of alpha-tocopherol that the SYN-E formula did (7.3 compared with 13.5 mg/L), the infants fed the LOWNAT-E formula had plasma alpha-tocopherol concentrations that were not significantly different from those of the infants fed the SYN-E formula. However, alpha-tocopherol intakes in the study population, when expressed as mg 2R-tocopherol isomers consumed/d, correlated with plasma alpha-tocopherol (r = 0.20, P = 0.02) and the ratio of plasma alpha-tocopherol to lipids (r = 0.19, P = 0.03). There were no significant differences in antioxidant status between the 3 groups, but the LOWNAT-E group showed a trend toward lower plasma isoprostanes.

CONCLUSIONS:

This study supports the new definition for vitamin E given in the 2000 Dietary Reference Intakes and suggests that infants discriminate between RRR-alpha-tocopheryl acetate and all-rac-alpha-tocopheryl acetate. All 3 infant formulas supported adequate vitaminE status.