Search

Background: Although ascorbic acid (AA) increases dietary iron bioavailability, there has been no food-based community trial of its efficacy in improving iron status. Objective: The objective was to assess the efficacy of 25 mg AA as agua de limon (limeade), consumed with each of 2 daily meals, in improving the iron status of iron-deficient women. Design: Two rural Mexican populations were randomly assigned to an AA or a placebo group, each with 18 iron-deficient women. The AA group was given 500 mL limeade containing 25 mg AA twice a day, 6 d/wk, for 8 mo. The placebo group was given a lime-flavored beverage free of AA or citric acid. Beverages were consumed within 30 min of 2 main daily meals. Data were collected on morbidity (3 times/wk), dietary intake (on 6 d), socioeconomic status, parasites (twice), medical history, and response to treatment. Blood samples at 0, 2, 4, 6, and 8 mo were analyzed for hemoglobin, plasma AA, plasma ferritin, transferrin receptors, and C-reactive protein. Results: AA intake was significantly (P < 0.0001) higher in the AA group, but nonheme iron, heme iron, and phytic acid intakes did not differ significantly. Plasma AA was significantly (P < 0.01) higher in the AA group at 2, 4, 6, and 8 mo. There were no final differences between groups in hemoglobin, plasma ferritin, or transferrin receptor concentrations or in the ratio of transferrin receptors to plasma ferritin after control for initial concentrations. Conclusion: Increasing dietary AA by 25 mg at each of 2 meals/d did not improve iron status in iron-deficient women consuming diets high in phytate and nonheme iron. KEY WORDS Iron deficiency, bioavailability, ascorbic acid, ferritin, transferrin receptors, women, community trial, rural Mexico

Background: Weaning foods frequently contain phytate, an inhibitor of iron and zinc absorption, which may contribute to the high prevalence of iron and zinc deficiency seen in infancy. Objective: The objective was to investigate whether either an extensive reduction in the phytate content of infant cereals or the use of milk-based, iron-fortified infant formula would improve iron and zinc status in infants. Design: In a double-blind design, infants (n = 300) were randomly assigned to 3 cereal groups from 6 to 12 mo of age: commercial milk-based cereal drink (MCD) and porridge (CC group), phytate-reduced MCD and phytate-reduced porridge (PR group), or milk-based infant formula and porridge with the usual phytate content (IF group). Venous blood samples were collected at 6 and 12 mo. Dietary intake was recorded monthly. After the intervention, 267 infants remained in the analysis. Results: Hemoglobin concentrations of < 110 g/L, serum ferritin concentrations of < 12 [micro]g/L, and serum zinc concentrations of < 10.7 [micro]mol/L had overall prevalences at baseline and 12 mo of 28% and 15%, 9% and 18%, and 22% and 27%, respectively. After the intervention, there were no significant differences in any measure of iron or zinc status between the CC and the PR groups. However, hemoglobin was significantly higher (120 g/L compared with 117 g/L; P = 0.012) and the prevalence of anemia was lower (13% compared with 23%; P = 0.06) in the PR group than in the IF group, which could be explained by differences in daily iron intake between the 2 groups. Conclusion: Extensive reduction in the phytate content of weaning cereals had little long-term effect on the iron and zinc status of Swedish infants. KEY WORDS Infants, cereals, iron, zinc, phytate, randomized controlled trial, weaning, Sweden