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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

Background: Practical and accurate methods for quantifying the soft tissue mineral component of multicomponent fat-estimation models are needed. Objectives: The aims were to develop a new complete model for estimating soft tissue minerals based on measured total body water (TBW) and extracellular water (ECW) and a simplified new model based on TBW measurements only and to compare these estimates with those determined with 2 traditional models (ie, the Brozek and Selinger models) and with criterion estimates based on in vivo neutron activation (IVNA) analysis. Design: The subjects were 156 healthy adults and 50 patients with AIDS. Total body potassium, sodium, chlorine, and calcium were measured by IVNA; TBW by [sup.3][H.sub.2]O or [D.sub.2]O dilution; ECW by bromide dilution; and bone mineral by dual-energy X-ray absorptiometry. Results: The mean ([+ or -] SD) mass of total-body soft tissue minerals in healthy adults was 467 [+ or -] 62 g with the IVNA model, 492 [+ or -] 62 g with the new model, and 487 [+ or -] 59 g with the simplified new model. Compared with the IVNA model, the complete and simplified new models overestimated soft tissue minerals by 5.4% and 4.6% (both P < 0.001), respectively. In contrast, the Brozek and Selinger models overestimated overall mean soft tissue minerals by 35% and 99% (both P < 0.001), respectively. Overall results for soft tissue mineral prediction with the 2 new models were less satisfactory for the patients with AIDS, although the results were better than those with the traditional models. Conclusions: The physiologically formulated complete new model for estimating soft tissue minerals provides the opportunity to upgrade the accuracy of current multicomponent models for estimating total body fat. KEY WORDS Extracellular water, intracellular water, body composition, multicomponent methods, neutron activation analysis, soft tissue mineral, AIDS

Leukemia is a cancer of the bone marrow resulting in excess production of disease-fighting white blood cells. Sixteen children being treated for leukemia with chemotherapy suffered from bone pain, abnormal gait, and unusual bone fractures. During treatment and six months later, their blood and urine were analyzed for calcium and magnesium. Their blood was analyzed for vitamin D, a hormone that triggers the release of calcium from bones (parathyroid hormone), and a substance related to the level of bone calcium (osteocalcin). Bone mineral content (weak bones are poor in minerals like calcium) and width of a bone of the forearm were measured. During chemotherapy, mild shortages of calcium (8 cases) and magnesium (9 cases) were found. Excess calcium and a lack of magnesium were also seen in urine specimens. Levels of osteocalcin in the blood correlated with magnesium levels in the blood. Oral magnesium supplements brought blood levels of magnesium, calcium, and osteocalcin back to normal. Blood levels of vitamin D were too low to detect in 12 out of 13 patients undergoing chemotherapy and in seven out of 13 patients not undergoing chemotherapy. Levels of an enzyme associated with the ability to metabolize phosphorus (alkaline phosphatase) increased significantly after therapy, and parathyroid hormone levels were normal in all cases. The ratio of bone mineral content to bone width was low (below the 30th percentile adjusted for age and gender) in 70 percent of these children. Alterations in magnesium, calcium, and vitamin D metabolism in children undergoing chemotherapy for leukemia may result in difficulties of bone formation and growth.