Concomitant supplemental vitamin A enhances the response to weekly supplemental iron and folic acid in anemic teenagers in urban Bangladesh

Background: Iron deficiency is the most common micronutrient deficiency and affects >2 billion persons worldwide, leading to anemia in >40% of women of reproductive age in the developing world. Objective: The objective was to determine whether weekly supplementation with iron and folate would reduce the frequency of anemia in teenage women in urban Bangladesh before they became pregnant. Design: Participants with a hemoglobin concentration of 80–120 g/L were entered into a randomized, double-blind, placebo-controlled trial and received supplements of placebo, vitamin A, iron + folic acid, or iron + folic acid + vitamin A weekly for 12 wk. The supplements contained 2.42 mg vitamin A (retinol) as retinyl palmitate, 120 mg elemental Fe as ferrous sulfate, and 3.5 mg folic acid. Results: Hemoglobin concentrations increased significantly more after supplementation with iron + folic acid or iron + folic acid + vitamin A than after either the placebo or vitamin A alone. There was a significantly greater increase in hemoglobin after iron + folic acid + vitamin A than after iron + folic acid, but the additional effect disappeared after adjustment for baseline hemoglobin, serum vitamin A, and ferritin and the number of supplements taken. Those with the lowest baseline hemoglobin had the greatest increase in hemoglobin. Compared with the placebo, iron + folic acid + vitamin A reduced anemia by 92%, iron deficiency by 90%, and vitamin A deficiency by 76%. Conclusion: There may be significant health benefits from a program that enhances the nutritional status of iron, folate, and vitamin A in poor urban young women before they become pregnant.