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Nutritional rickets resulting from calcium insufficiency is common in Nigeria and high dietary phytate is thought to inhibit calcium and zinc absorption. We compared the effects of a high-phytate meal and enzymatic dephytinization on calcium and zinc absorption in Nigerian children with and without rickets. Nineteen children with rickets and 15 age-matched control children, aged 2-10 y, were given calcium (600 mg/d) and ergocalciferol (1250 [micro]g/wk). After 6 wk, calcium and zinc absorption were measured in both groups with and without maize porridge using stable isotopes. One week later, absorption measurements were repeated to assess the effects of enzymatic dephytinization and fermentation of the maize porridge. The phytate concentration of maize porridge (3.87 [+ or -] 0.38 g/kg wet weight) was reduced by enzymatic dephytinization (2.83 [+ or -] 0.41 g/kg; P < 0.001) but not by fermentation (3.35 [+ or -] 0.27 g/kg; P = 0.08). Calcium and zinc absorption were unaffected by the presence of rickets or by fermentation of maize porridge. Calcium absorption was greater.with a meal (61.3 [+ or -] 25.1%) than without (27.8 [+ or -] 14.6%; P < 0.001). Zinc absorption was lower with a meal (16.2 [+ or -] 8.0%) than without (63.4 [+ or -] 23.9%; P < 0.001). Enzymatic dephytinization increased relative zinc absorption from a meal by 101 [+ or -] 81% (P < 0.001) but did not affect calcium absorption. Rickets was not associated with impaired calcium or zinc absorption. Calcium absorption was enhanced by maize porridge, but zinc absorption was reduced. Enzymatic dephytinization increased zinc absorption. Multiple strategies may be required to optimize calcium and zinc absorption in deficient populations.

Calcium absorption efficiency and bone mineral mass are increased in adolescents who regularly consume inulin-type fructans (ITF). The mechanism of action in increasing absorption is unknown but may be related to increased colonic calcium absorption. We conducted a study in young adults designed to evaluate these mechanisms with a kinetic technique using [sup.42]Ca orally and [sup.46]Ca dosed i.v. Those who responded to 8 wk of supplementation with 8 g of a mixed short and long degree of polymerization ITF by increasing their calcium absorption had kinetic measurements analyzed to evaluate the time course of absorption. The area under the curve of the oral tracer in the blood during the 26 h after dosing was calculated and the time dependence of increased absorption determined. Eight young adults (of 13 studied), with mean calcium intake ~900 mg/d, responded to the ITF with an increased calcium absorption of at least 3%. In responders, absorption increased from 22.7 [+ or -] 11.3% to 31.0 [+ or -] 15.3%. Colonic absorption, defined as absorption that occurred >7 h after oral dosing, represented 69.6 [+ or -] 18.6% of the increase, or 49 [+ or -] 28 mg/d. These findings suggest that, in those who respond to ITF, its effects on calcium absorption occur principally in the colon. This benefit to ITF may be especially important when absorption in the small intestine is impaired for anatomic or physiological reasons.

Few studies have evaluated iron absorption in small children after the first year of life. Our objectives were to examine the relations among iron intake, iron absorption, and iron status in a group of healthy children. We studied 28 children, ages 12 to 48 mo, after a 7-d home adaptation to a diet representative of their usual daily mineral intake. A multi-tracer stable isotope study was performed to assess iron absorption both from a meal ([sup.58]Fe) and from a reference iron dose ([sup.57]Fe) given with ascorbic acid without a meal. Iron intake was 6.9 [+ or -] 2.4 mg, approximately the 35th percentile of typical U.S. intakes. Absorption of [sup.58]Fe was related to serum ferritin ([r.sup.2] = 0.319, P = 0.0018) and more so to reference dose iron absorption ([r.sup.2] = 0.653, P < 0.0001). Iron absorption was negatively correlated with zinc intake ([r.sup.2] = 0.090, P = 0.0049) but was not correlated with iron intake (P = 0.20). However, zinc intake was not correlated with measures of iron status, including reference dose iron absorption and serum ferritin ([r.sup.2] < 0.1, P > 0.25). Total absorbed iron was similar to needs estimated by the Institute of Medicine. We conclude that iron absorption in young children is more closely related to iron status than to iron intake. Reference dose iron absorption may be superior to serum ferritin as a surrogate measure for iron status in this age group. Although zinc intake may affect iron absorption from a meal, it does not appear to have a detectable effect on overall iron status in otherwise well-nourished children.

Increasing calcium absorption and bone calcium accretion to levels above those achieved by human milk-fed, full-term infants is possible with infant formulas. However, no data support such a goal or suggest that it is beneficial to short- or long-term bone health. Small differences in the bioavailability of calcium between infant formulas are unlikely to have long-term consequences. Long-term studies of the effects of infant feeding type on ultimate bone mass are needed. For now, the vitamin-replete breast-fed infant's rate of calcium accretion during the first year of life should be the standard targeted for infant formulas. Key words: bone mineral content, calcium absorption, human milk, minerals

Iron absorption in adults is regulated by homeostatic mechanisms that decrease absorption when iron status is high. There are few data, however, regarding the existence of a similar homeostatic regulation in infants. We studied 2 groups of human milk-fed infants using [sup.57]Fe (given as ferrous sulfate without any milk) and [sup.58]Fe (given at the time of a breast-milk feeding) stable isotopes to determine whether healthy infants at risk for iron deficiency would regulate their iron absorption based on their iron status. We studied 20 Peruvian infants at 5-6 mo of age and 18 infants at 9-10 mo of age. We found no effect of infant hemoglobin concentration on iron absorption with 5-6 mo--old infants absorbing 19.2 [+ or -] 2.1% and 9- to 10-mo-old infants absorbing 25.8 [+ or -] 2.6% of the [sup.57]Fe dose. For [sup.58]Fe, 5- to 6-mo-old infants absorbed 42.6 [+ or -] 5.0% and 9 to 10-mo--old infants absorbed 51.9 [+ or -] 10.3%. Following log transformation, iron absorption from [sup.57]Fe (r = -0.61, P = < 0.001) and [sup.58]Fe (r = -0.61, P = < 0.001) were inversely correlated to serum ferritin (S-Ft). For both the [sup.57]Fe and [sup.58]Fe doses, infants with S-Ft < 12 mg/L (n = 11 ) had significantly higher iron absorption than those with S-Ft > 12 mg/L. We concluded that iron absorption in infants is related to iron status as assessed by serum ferritin but not hemoglobin concentration. Infants with low iron status upregulate iron absorption from breast milk at both 5-6 and 9-10 mo of age.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jada.2006.03.004 Byline: Keli M. Hawthorne, Karen Moreland, Ian J. Griffin, Steven A. Abrams Abstract: While much research has focused on intake and eating behaviors of young adolescents, few studies have examined their knowledge of the Nutrition Facts label. The goals of this project were to assess the understanding of Nutrition Facts labels and the response of young adolescents to an educational program about Nutrition Facts labels. Thirty-four young adolescents participated by answering a short questionnaire and taking a pretest about Nutrition Facts labels and their food choices, which involved using actual Nutrition Facts labels from foods typically eaten by adolescents. Then the subjects participated in a short educational program on how to read the Nutrition Facts label. This was followed by a posttest. Initial knowledge of the basic use of the Nutrition Facts label was marginal, with only 6.65 (standard deviation=2.23) or [approximately equal to]55% of pretest questions answered correctly. However, the subjects' scores improved significantly to 8.32 (standard deviation=2.01) or [approximately equal to]70% correct on the posttest (P<0.0001, Fisher's exact test) after the educational session. In conclusion, young adolescents can learn how to read and understand the Nutrition Facts labels through educational sessions.

Calcium supplementation has been shown to increase bone mineralization in children and adolescents. However, catch-up mineralization later in puberty appears likely if intake is consistent with usual average intakes in the United States. Ultimately, individualized risk assessment will be developed based on genetic and lifestyle factors that can be used to guide optimal calcium intake during childhood. Key words: calcium absorption, dietary requirements, puberty, bone mass

Stable isotope absorption studies of iron have been limited by the high cost and limited availability of isotope ratio analysis using thermal ionization MS (TIMS). The development of high-resolution double focusing inductively coupled plasma MS (ICP-MS) may permit more cost-efficient sample analysis due to its high throughput, lower cost, easy sample pretreatment, and greater availability. Our objective was to develop an ICP-MS methodology for the measurement of iron isotope ratios using very small blood volumes. We developed a technique using multiple iron-nickel mixing standard solutions to adjust for nickel interference calibration. RBC samples from human subjects previously given [.sup.58]Fe and [.sup.5]7Fe were analyzed for iron isotope ratios and compared with our current methodology (TIMS). Reproducibility of iron isotope ratios provided external relative SD < 0.5 and 0.7% (1 SD) for [.sup.57]Fe/[.sup.54]Fe and [.sup.58]Fe/[.sup.54]Fe, respectively. Iron isotope ratios from ICP-MS analysis did not differ from those from TIMS based on statistical analyses, nor did the calculated iron absorption values. The mean and SD of iron absorption did not differ when measured by TIMS or ICP-MS. A 2-[mu]L RBC sample was sufficient for ICP-MS iron isotope ratio analysis with an internal relative SD < 0.5% and analytical time < 5 min. This technique may assist groups in increasing their use of stable isotope methods to assess iron absorption in infants and children. KEY WORDS: * inductively coupled plasma MS * iron absorption * isobaric interference * mass bias * stable isotopes

The addition of milk and milk-based products to the diets of individuals subsisting on plant-based diets was reported to have positive effects on nutritional status and functional outcomes such as growth, morbidity, and cognition. We examined the effect of the addition of milk or yogurt on the bioavailability of zinc and iron from a plant-based rural diet. The subjects were 48 Mexican women (30.9 [+ or -] 5.7 y) who habitually consumed a plant-based diet. The women were assigned to 1 of 3 groups: 1) the typical rural Mexican diet, 2) that diet with milk added, or 3) that diet with yogurt for 13 d. Zinc absorption was measured after extrinsically labeling meals with 87Zn and an i.v. dose of [sup.70]Zn; iron absorption was measured by extrinsically labeling meals with [sup.67]Fe and a reference oral dose of [sup.57]Fe. Including milk and yogurt in the diet increased zinc absorption by 50 and 68%, respectively (P < 0.05). The 3 groups did not differ in the percentage iron absorption. The total amount of zinc absorbed was increased (P < 0.05) by 70% when milk was added to the meal and 78% when yogurt was added. The total amount of iron absorbed did not differ among the groups. The addition of milk and yogurt to a plant-based diet high in phytate increases zinc bioavailability without affecting iron bioavailability. KEY WORDS: * nutrient bioavailability * zinc absorption * iron absorption * Mexican diets * stable isotopes

After 1 y of distributing a milk-based fortified weaning food provided by the Mexican social program PROGRESA, positive effects on physical growth, prevalence of anemia, and several vitamin deficiencies were observed. There was no effect on iron status, which we hypothesized was related to the poor bioavailability of the reduced iron used as a fortificant in PROGRESA. The objective of this study was to compare the iron bioavailability from different iron sources added as fortificants to the weaning food. Children (n 54) aged 2-4 y were randomly assigned to receive 44 g of the weaning food fortified with ferrous sulfate, ferrous fumarate, or reduced iron + [Na.sub.2]EDTA. Iron absorption was measured using an established double-tracer isotopic methodology. Iron absorption from ferrous sulfate (7.9 [+ or -] 9.8%) was greater than from either ferrous fumarate (2.43 [+ or -] 2.3%) or reduced iron + [Na.sub.2]EDTA (1.4 [+ or -] 1.3%) (P < 0.01). The absorption of [log-.sup.58] Fe sulfate given with the iron source correlated with serum ferritin (s-ferritin) concentration (n = 13, r = 0.63, P = 0.01) and [log-.sup.57] Fe absorption (reference dose) (n = 14, r = -0.52, P = 0.02). Absorption from ferrous fumarate and reduced iron + Na2EDTA did not correlate with s-ferritin or absorption of [sup.57] Fe. The recommended daily portion of the fortified complementary food provides an average of 0.256, 0.096, 0.046 mmol (1.44, 0.54, and 0.26 mg) of absorbed iron, if fortified with sulfate, fumarate and reduced iron + [Na.sub.2] EDTA, respectively. Ferrous sulfate was more bioavailable than either ferrous fumarate or reduced iron + [Na.sub.2]EDTA when added to the milk-based fortified food and more readily met the average daily iron requirements for children 2-3 y of age. KEY WORDS: * iron absorption * stable isotopes * fortification

For full-term infants in the first 6 months of life, exclusive breastfeeding remains the nutritional standard for calcium intake. However, unsupplemented human milk does not meet the nutritional requirements for growth of the very-low-birth-weight (< 1500 g) infant. Methods for human milk fortification have been evaluated, and recent studies have demonstrated the safety of these fortifiers. Key words: human milk, fortification, minerals, prematurity

Rice flour was proposed as a vehicle for iron and zinc fortification in Sri Lanka. Although widely consumed, rice flour has not been evaluated as a fortified food, and the absorption of minerals including iron and zinc from this flour is unknown. Determination of the bioavailability of these nutrients is a critical step before commencing a fortification program. We randomly divided 53 Sri Lankan schoolchildren ages 6-10 y into 4 groups that consumed a local dish prepared with 25 g of fortified rice flour labeled with one of the following: 1) [sup.58]FES[O.sub.4] 2) [sup.58]FES[O.sub.4] + [Na.sub.2]EDTA 3) [sup.58]FES[O.sub.4] + [sup.67].ZnO or, 4) [sup.58]FES[O.sub.4] + [Na.sub.2]EDTA + [sup.67]ZnO. The levels of iron and zinc were 60 mg/kg; the rice flour also contained folate at 2 mg/kg in each group. [Na.sub.2]EDTA was added at a Fe:[Na.sub.2]EDTA, 1:1 molar ratiO. A total of 48 children completed the trial. Absorption of [sup.58]Fe from a meal was significantly greater (P < 0.01) in the groups administered FeS[O.sub.4] + [Na.sub.2]EDTA (4.7 [+ or -] 3.6%) than in those administered FeS[O.sub.4] without [Na.sub.2]EDTA (2.2 [+ or -] 1.3%). Fractional absorption of Zinc was 13.5 [+ or -] 6.0% in the FeS[O.sub.4] + [Na.sub.2]EDTA group and 8.8 [+ or -] 2.0% in the FeS[O.sub.4] group (P = 0.037). Although zinc absorption was low, our results demonstrated a benefit in using [Na.sub.2]EDTA to improve both iron and zinc absorption. We conclude that the fortification of rice flour is feasible, although additional strategies such as dephytinization or an increase in the level of iron and zinc fortification should be considered to obtain a higher proportion of the daily requirement of total absorbed iron and zinc. KEY WORDS: * fortification * rice flour * Sri Lanka * iron absorption * zinc absorption

The search for a reliable, convenient indicator of Zn status was the focus of research for several decades. Plasma Zn concentration is still the most widely used clinical measurement, despite the known problems of interpretation. More recently, researchers suggested that isotopically determined kinetic parameters, such as the exchangeable Zn pool (EZP), may more accurately and reliably reflect body Zn status. The objective of this study was to examine the relationship between net body Zn loss and gain during acute changes in dietary Zn intake with biochemical and kinetic indices of Zn status. Five men participated in an 85-d Zn depletion/repletion study. Net body Zn loss and gain were determined from the difference between dietary plus intravenously administered Zn and Zn excretion. Biochemical indicators of Zn status included plasma Zn, plasma alkaline phosphatase activity, and plasma retinol binding protein concentration. Following intravenous administration of [sup.70]Zn or [sup.67]Zn, a compartmental model was used to determine EZP mass, fractional Zn absorption, endogenous zinc excretion (EZE), and plasma Zn flux. The changes in total body zinc correlated best with changes in plasma Zn ([r.sup.2] = 0.826, P < 0.001), EZE ([r.sup.2] = 0.773, P < 0.001), and plasma Zn flux ([r.sup.2] = 0.788, P < 0.001). This study confirms that plasma Zn concentration is a valid indicator of whole-body Zn status in the absence of confounding factors; however, further research is needed to determine how kinetic parameters respond to conditions where plasma Zn concentration is known to be unreliable. KEY WORDS: zinc status biochemical indices * stable isotopes * kinetic analysis * compartmental model

The most sustainable way to eradicate iron deficiency is through food fortification. Elemental iron powders are commonly utilized as fortificants due to their low cost and few sensory problems. However, their bioavailability is unknown. Our goals were to measure the bioavailability of elemental iron in Mexican style corn masa flour tortillas and to evaluate the effects of [Na.sub.2]EDTA. We used a stable isotope of [H.sub.2]-reduced iron powder, with and without [Na.sub.2]EDTA in tortillas prepared with corn masa flour. Two groups of 5- to 7-y-old children (n = 12/group) were fed tortillas to which was added 3 mg/100 g of [H.sub.2]-reduced [sup.58]Fe with a mean particle size of 15 [micro]m. In one group, [Na.sub.2]EDTA was incorporated at a ratio of 1:2 mol/mol. The next day, [sup.57]Fe ascorbate was given as a reference dose. After 14 d, blood samples were analyzed for isotopic enrichment. When normalized to 40% absorption of the reference dose, the geometric mean ([+ or -] range 1 SD) bioavailability of reduced iron in tortilla was 3.8% (2.7-5.3). The addition of [Na.sub.2]EDTA, tended to increase it (P = 0.18) to 5.1% (2.8-9.2). This observed low absorption was compounded by the use of iron isotopes with smaller particle size (mean diameter 15 [micro]m) than typical of commercial elemental iron powder ( KEY WORDS: * elemental iron * iron bioavailability * corn masa flour * disodium EDTA * stable isotopes

Provision of the bone minerals and vitamin D as fortificants in food or as dietary supplements designed for older infants and toddlers in Latin America is likely to be beneficial and safe. Currently available data are inadequate to establish the precise amounts of these nutrients that would be required for such a supplement. These amounts would vary according to the local base diet. However, reasonable estimates can be made on the basis of current dietary recommendations as well as existing data on bioavailability and customary intake. The strongest case can be made for calcium and vitamin D supplementation. Because excessive dietary calcium can reduce zinc absorption as a result of interactive effects within the intestine, an appropriate ratio of calcium to zinc should be used, even if this means adding zinc as a fortificant or supplement. Magnesium supplementation may be appropriate in some circumstances but it cannot be routinely advocated at present. It is unlikely that phosphorus supplementation is needed for most population groups because of the relatively high usual dietary phosphorus intakes, primarily from phosphate salts added to carbonated beverages and as food preservatives. KEY WORDS: * human nutrition * bone mineral metabolism * rickets * mineral fortification of foods * iron * zinc * infants * young children

Due to their widespread acceptability, multinutrient-fortified foods and beverages may be useful in reducing micronutrient deficiencies, especially in developing countries. We studied the efficacy of a new fortified beverage in improving the nutritional status of children in Botswana. We screened 311 lower income urban school children, ages 6-11 y, in two primary schools near Gaborone. Children were given seven 240-mL servings weekly of either an experimental beverage (EXP) fortified with 12 micronutrients or an isoenergetic placebo drink (CON) for 8 wk. Weight, mid-upper arm circumference, hemoglobin, retinol, ferritin, vitamin B-12, folate and riboflavin status were measured at baseline and at the end of the study. Plasma zinc and serum transferrin receptors also were measured at study end. A total of 145 children in the EXP group and 118 in the CON group completed the trial. Using multivariate analysis, the changes in mid-upper arm circumference, weight for age and total weight were significantly better in the EXP group than in the CON group (P < 0.01). Ferritin, riboflavin and folate status were significantly better in the EXP group than in the CON group at study end (P < 0.01), but serum vitamin B-12 was not. Zinc was significantly higher and transferrin receptors were significantly lower at the conclusion of the study in the EXP group than in the CON group (P < 0.001). Mean plasma retinol concentrations, which were low ( KEY WORDS: * Africa * fortified beverage * micronutrient deficiency * undernutrition

Background Maternal vitamin D status during pregnancy and lactation is a modifiable factor that may influence offspring musculoskeletal outcomes. However, few randomized trials have tested the effects of prenatal or postpartum vitamin D supplementation on offspring bone and muscle development. Objectives The aim was to examine hypothesized effects of improvements in early-life vitamin D status on childhood musculoskeletal health in Dhaka, Bangladesh. Methods In a previously completed, double-blind, dose-ranging trial, healthy pregnant women (n  = 1300) were recruited at 17–24 weeks' gestation and randomly assigned to a prenatal/postpartum regimen of 0/0, 4200/0, 16,800/0, 28,000/0, or 28,000/28,000 IU cholecalciferol (vitamin D3)/wk until 26 wk postpartum. In this new report, we describe additional follow-up at 4 y of age (n  = 642) for longer-term outcomes. Bone mineral content (BMC) and areal bone mineral density (aBMD) were measured by DXA. Grip strength was tested using a hand-held dynamometer. The primary comparison was children of women assigned to 28,000 IU/wk prenatally compared with placebo. Differences are expressed as means and 95% CIs. Results Total-body-less-head (TBLH) BMC, TBLH aBMD, and grip strength were similar in the combined high-dose prenatal (28,000/0 and 28,000/28,000 IU/wk) compared with placebo groups (mean difference [95% CI] = 0.61 g [–10.90, 12.13], 0.0004 g/cm2 [–0.0089, 0.0097], and 0.02 kg [–0.26, 0.31], respectively). In dose-ranging analyses, TBLH BMC and aBMD, whole-body BMC and aBMD, and grip strength in each of the prenatal vitamin D groups were not significantly different from placebo (P  > 0.05 for all comparisons). Only head aBMD was greater in children of women assigned to the 28,000/28,000-IU regimen compared with placebo (mean difference [95% CI] = 0.024 g/cm2 [0.0009, 0.047], P  = 0.042); the effect was attenuated upon adjustment for child height, weight, and sex (P  = 0.11). Conclusions Maternal prenatal, with or without postpartum, vitamin D supplementation does not improve child BMC, aBMD, or grip strength at 4 y of age. The MDIG trial and present follow-up study were registered prospectively at www.clinicaltrials.gov as NCT01924013 and NCT03537443, respectively. [ABSTRACT FROM AUTHOR]

Nutritional rickets, an ancient disease that was thought to have been cured in the early part of the 20th century, has made an unexpected comeback in recent years throughout the world. Although the frequency of its occurrence is poorly documented, increasing case reports of rickets are apparently related to low dietary intake of vitamin D and calcium and decreased sunshine exposure. Greater awareness of this problem is needed, as are further data regarding vitamin D status and incidence of rickets among infants and toddlers. Routine provision of supplemental vitamin D to all breastfed infants remains controversial, but may become more widely recommended. Key Words: rickets, vitamin D, calcium, sunshine