Impact of vitamin D fortified milk supplementation on vitamin D status of healthy school children aged 10-14 years

Vitamin D deficiency is a major public health problem, needing immediate attention. We studied the effect of vitamin D fortification of milk in school children. Our results show that fortification of milk is safe and effective strategy to deal with widespread vitamin D deficiency.

INTRODUCTION

Vitamin D deficiency among school children and adolescents is a well-documented major public health problem, needing immediate attention. To assess the effect of vitamin D fortified milk on serum 25 hydroxy vitamin D [S.25(OH)D] levels, we carried out a prospective double-blind randomized control trial in apparently healthy school children, aged 10-14 years.

METHODS

Of 776 subjects recruited out of 796 who consented, 713 (boys-300; girls-413) completed the study. Subjects were randomized into three groups. Group A (n = 237) received 200 ml of unfortified milk per day while group B (n = 243) and group C (n = 233) received 200 ml of milk fortified with 600 IU (15 μg) and 1,000 IU (25 μg) of vitamin D per day for 12 weeks. Serum calcium, phosphate, alkaline phosphatase, S.25(OH)D, and urinary calcium/creatinine ratio were estimated at baseline and after supplementation.

RESULTS

Hypovitaminosis D [25(OH)D < 20 ng/ml] was observed in 92.3 % subjects with mean S.25(OH)D level of 11.69 ± 5.36 ng/ml. There was no significant difference in S.25(OH)D levels among the three groups at baseline. The mean percentage change in S.25(OH)D level in groups B (137.97 %) and C (177.29 %.) were significantly greater than group A (-5.25 %). The percentage of subjects having S.25(OH)D levels >20 ng/ml following supplementation were 5.9 % in group A, 69.95 % in group B, and 81.11 % in group C in comparison to 6.32 %, 4.9 % and 12 %, respectively, at baseline.

CONCLUSION

Fortification of milk with vitamin D is an effective and safe strategy in improving S.25(OH)D levels in children aged 10-14 years.

The effect of growth hormone deficiency on size-corrected bone mineral measures in pre-pubertal children

Growth hormone deficiency (GHD) in children has been frequently perceived to be a cause of low bone mass accrual. The confounding effects of poor growth limit the interpretation of prior studies of bone health in GHD. We studied size-corrected bone mineral measures in 30 pre-pubertal GHD children and 75 healthy controls. Our study shows that size-corrected whole-body bone mineral content of GHD children were comparable with controls.

INTRODUCTION

The purpose of this study is to evaluate the effects of GHD on size-corrected bone measures at the lumbar spine (LS) and the whole body (WB).

METHODS

LS bone area (BA), LS bone mineral content (BMC), WB BA, WB BMC, and lean body mass (LBM) were measured in 30 pre-pubertal GHD children and 75 controls by dual-energy X-ray absorptiometry. Multiple linear regressions were used to calculate size-corrected (Sc) LS BA(Sc), LS BMC(Sc), WB BA(Sc), and WB BMC(Sc) from control subjects using height and age as independent variables. Furthermore, the relationship between muscle and bone was studied by first assessing LBM for height (LBM(Ht)) and then determining WB BMC for LBM (WB BMC(LBM)). All values were converted to Z-scores and compared with the control.

RESULTS

At diagnosis, WB BMC(Sc) Z-score of GHD children was not significantly different from controls. However, mean Z-scores of LS BA(Sc) (-0.89 ± 0.84, p < 0.0001), LS BMC(Sc) (-0.70 ± 1.1, p < 0.001), WB BA(Sc) (-0.65 ± 1.0, p < 0.006), and LBM(Ht) (-0.66 ± 1.7, p < 0.01) were significantly reduced, and WB BMC(Lbm) (0.78 ± 1.5, p < 0.003) was significantly higher in GHD children than controls.

CONCLUSION

Size-corrected WB BMC of GHD children were comparable with controls, and bones were normally adapted for muscle mass. Determinants of bone strength which may primarily be affected by GHD are muscle mass, bone size, and geometry rather than bone mass.