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

Abstract

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. 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. 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. 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. 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.