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The importance of vitamin D for ensuring the health of children has long been understood. Over time, however, dietary recommendations for vitamin D intake have varied, with some eras seeing higher levels recommended and some lower. Remarkably, the current recommendations from the Institute of Medicine are not much different from those released with the first edition of the recommended dietary allowances in 1941. The present review examines the evolution of vitamin D recommendations over time and considers the differences and potential consequences related to the various recommendations in effect today. In considering strategies to evaluate the vitamin D status of children and efforts to assure its adequacy, individual caregivers and policy makers need to consider carefully the costs and potential risks of different screening strategies involving blood testing in children and of supplementation. More data on the long-term risks and benefits are needed before widespread screening or supplementation can be advocated. [ABSTRACT FROM AUTHOR]

Bone minerals and vitamin D are crucial for infants and small children. Human milk has little vitamin D, and supplemental vitamin D must be given to all infants either via drops or as contained in infant formula or foods. The calcium and phosphorus in human milk are adequate for infants in the first six months of life, with supplemental minerals coming from weaning foods after six months. Long-term benefits to providing bone minerals at greater levels than in human milk have not been shown. There is no evidence to support high-dose bone mineral supplementation or high-dose vitamin D supplementation in infancy, and controlled trials are needed before these can be advocated. [ABSTRACT FROM AUTHOR]

Nutritional rickets has long been considered a disease caused by vitamin D deficiency, but recent data indicate that inadequate dietary calcium intake is an important cause of rickets, particularly in tropical countries. Children with rickets due to calcium deficiency do not have very low 25(OH)D concentrations, and serum 1,25(OH)D values are markedly elevated. Studies of Nigerian children with rickets demonstrated they have high fractional calcium absorption. A high-phytate diet was demonstrated to increase calcium absorption compared with the fasting state, and enzymatic dephytinization did not significantly improve calcium absorption. When given vitamin D, children with rickets have a marked increase in 1,25(OH)D concentrations without any change in fractional calcium absorption. No positive relationship was found between fractional calcium absorption and serum 25(OH)D concentrations in children on low-calcium diets. More research is needed to understand the interaction between calcium and vitamin D and the role of vitamin D in calcium absorption. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 (<0.7 micro mol/L) in both groups, did not change. We conclude that a micronutrient-fortified beverage may be beneficial as part of a comprehensive nutritional supplementation program in populations at risk for micronutrient deficiencies. [ABSTRACT FROM AUTHOR]

The article offers information on the modified dietary guidelines for calcium and vitamin D for children and adults provided by the U.S. Institute of Medicine (IOM) for 2011. According to a report released by the IOM, the pediatric recommended dietary allowance (RDA) values for calcium is 1300 milligrams per day for children aged 9 to 18 years and 400 international units per day. It announces that the final issue of the dietary recommended intake (DRI) will be released in 2011.

Abstract: The Institute of Medicine Committee to Review Dietary Reference Intakes for Calcium and Vitamin D comprehensively reviewed the evidence for both skeletal and nonskeletal health outcomes and concluded that a causal role of calcium and vitamin D in skeletal health provided the necessary basis for the 2011 Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) for ages older than 1 year. For nonskeletal outcomes, including cancer, cardiovascular disease, diabetes, infections, and autoimmune disorders, randomized clinical trials were sparse, and evidence was inconsistent, inconclusive as to causality, and insufficient for Dietary Reference Intake (DRI) development. The EAR and RDA for calcium range from 500 to 1,100 and 700 to 1,300 mg daily, respectively, for ages 1 year and older. For vitamin D (assuming minimal sun exposure), the EAR is 400 IU/day for ages older than 1 year and the RDA is 600 IU/day for ages 1 to 70 years and 800 IU/day for 71 years and older, corresponding to serum 25-hydroxyvitamin D (25OHD) levels of 16 ng/mL (40 nmol/L) for EARs and 20 ng/mL (50 nmol/L) or more for RDAs. Prevalence of vitamin D inadequacy in North America has been overestimated based on serum 25OHD levels corresponding to the EAR and RDA. Higher serum 25OHD levels were not consistently associated with greater benefit, and for some outcomes U-shaped associations with risks at both low and high levels were observed. The Tolerable Upper Intake Level for calcium ranges from 1,000 to 3,000 mg daily, based on calcium excretion or kidney stone formation, and from 1,000 to 4,000 IU daily for vitamin D, based on hypercalcemia adjusted for uncertainty resulting from emerging risk relationships. Urgently needed are evidence-based guidelines to interpret serum 25OHD levels relative to vitamin D status and intervention. [Copyright &y& Elsevier]

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(2)EDTA. Iron absorption was measured using an established double-tracer isotopic methodology. Iron absorption from ferrous sulfate (7.9 +/- 9.8%) was greater than from either ferrous fumarate (2.43 +/- 2.3%) or reduced iron + Na(2)EDTA (1.4 +/- 1.3%) (P < 0.01). The absorption of log-(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-(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 (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(2)EDTA, respectively. Ferrous sulfate was more bioavailable than either ferrous fumarate or reduced iron + Na(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. [ABSTRACT FROM AUTHOR]