Weekly micronutrient supplementation to build iron stores in female Indonesian adolescents

Different supplementation schemes to build iron stores in female Indonesian adolescents were investigated. Subjects were 273 high-school girls allocated randomly to four treatment groups. During a 3-mo period one group received 60 mg Fe, 750 micrograms retinol, 250 micrograms folic acid, and 60 mg vitamin C per day; a second group received 60 mg Fe, 6000 micrograms retinol, 500 mg folic acid, and 60 mg vitamin C once a week; a third group received 120 mg Fe and the same amount of the other three micronutrients as the second group once a week; and a fourth group received only placebos. All subjects were dewormed and supplement allocation was double blind. Blood samples were collected at baseline, after 2 and 3 mo of supplementation, and 6 mo after the last supplement. After 2 mo of supplementation, groups supplemented weekly and daily showed similar significant improvements (P < 0.001) in hemoglobin and retinol concentrations, and supplementation for 3 instead of 2 mo did not significantly increase these two indicators. After 3 mo, the increase in ferritin was approximately equal to 27 micrograms/L in the daily and 14-15 micrograms/L in the weekly groups (P < 0.001), the latter having a final concentration of 42-45 micrograms/L. At 6 mo postsupplementation there were no significant differences among daily and weekly groups, but the ferritin concentration was still approximately equal to 10-12-micrograms/L higher (P < 0.001) than in the placebo group. The group supplemented weekly with 60 mg Fe complained less about side effects than the other supplemented groups (P < 0.05). Weekly supplementation with 60 mg Fe and 6000 micrograms retinol for 3 mo was optimal for improving the iron status of the adolescents for approximately equal to 9 mo.