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ABSTRACT

 Background and Aim: Although osteoporosis is not common in children and adolescents bone mineral density (BMD) studies in early life can be good predictors for this disease in the future. The aim of this study was to provide reference data of Dual X-ray Absorptiometry (DXA) for a population aged 10 to 20 years, in Tehran.

 Materials and Methods: 187 healthy people between 10-20 years of age were entered into this study randomly. Using DXA, BMD of femoral neck and lumbar vertebrae (L1-L4) (anteroposterior) were measured. Stage of puberty was determined and questionnaires about daily calcium intake were filled out. Serum levels of calcium, phosphate, vitamin D, parathyroid hormone and alkaline phosphatase were determined in all participants.

 Results: BMD values showed a positive correlation with age, height, weight and puberty stage. Calcium intake showed a correlation with BMD values of femoral neck, but not of lumbar region. In lumbar region, girls up to age of 18 had higher BMD values. In femoral region, boys had higher BMD values in all age groups. In neither regions, however, these differences were statistically significant. BMD increment at different stages of^�sexual development was statistically different only in stages 3 and 4 of puberty for both sexes in femoral and lumbar regions.

 Conclusion: Normative value curves developed in this study can serve as standards to predict bone mineral density.

Key words: Bone mineral density, Normative values, Calcium intake

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Background and Aim: Vitamin D is essential for the health of pregnant women and their newborns. The aim of this study was to determine the relationship between the outcome of pregnancy and maternal calcium and vitamin D intake. Materials and Methods: This cross-sectional study included 449 healthy pregnant women at the time of delivery and also their newborns after delivery. Maternal and neonatal anthropometric data were collected and Calcium and Vitamin D intake was determined. The mean values for vitamin D and calcium intake in mothers were 2.26±1.87 µg/d and 816.284±370.47 mg/d respectively. Results: Our findings showed that, the mean Apgar score and height of the newborns whose mothers had adequate calcium and vitamin D intake were higher than those of infants of mothers with inadequate intake (p=0.04, p=0.03 respectively). Conclusions: Our study showed a significant correlation between adequate maternal calcium and vitamin D intake and appropriate neonatal birth weight, height and one-minute Apgar score. We found that mothers with adequate intake of calcium and vitamin D had greater weight gain. Therefore proper nutritional plans for pregnant women are necessary. Consumption of foods rich in calcium and vitamin D, in particular dairy products, fortification of foods and addition of supplements to diet regimen of the population at risk of developing such nutritional deficiencies should be taken into consideration.