Objective: To determine whether supplementation of vitamin A and/or zinc (Z
n) improved serum levels of these nutrients and/or height and weight gains
in preschool children, 22 to 66 months, living in Belize, Central America.
Methods: Subjects received either Zn, vitamin A, Zn and vitamin A or a plac
ebo, (70 mg Zn and/or 3030 RE vitamin A, once per week) for 6 months in a 2
x 2 factorial design. Forty-three children, from a population of 104 presc
reened, completed the study; they were selected, prior to treatment, for lo
w/marginal serum concentrations of these micronutrients.
Results: Serum Zn levels were greater (16%, p < 0.001) for those who receiv
ed Zn. In contrast, after vitamin A treatment there were no differences in
serum vitamin A among groups. Although increases in height (+4.4 cm, p < 0.
001) and weight (+0.79 kg, p < 0.001), compared with baseline values, were
numerically greatest for children who received both supplements, only the v
itamin A supplementation effect was significant, resulting in increased hei
ght (+1.4 cm, p < 0.002) and greater weight gain (+0.15 kg, p < 0.03) compa
red to those receiving no vitamin A. Vitamin A supplementation alone signif
icantly increased (p < 0.001) hemoglobin concentration.
Conclusion: The results suggest that the preschool children in this study,
prescreened for low/marginal serum concentrations from a larger population
prior to treatment, were enduring inadequate vitamin A and, to a lesser deg
ree, Zn nutriture. Height and weight gain were significantly increased in t
he subjects who received a single weekly supplement 3030 RE of vitamin A.