Effects of vitamin D fortified milk on vitamin D status in Mongolian school age children.

Mongolians are at high risk for vitamin D deficiency because of their residence at northern latitude, reduced exposure to UV-B rays during the winter months, and a low availability of vitamin-D fortified foods. We performed a pilot study in May 2005 to estimate the prevalence of hypovitaminosis D in Mongolian school age children and to determine the feasibility of conducting a longer and larger trial with fortified milk and vitamin D supplements. In a group of 46 Mongolian children (22 girls and 24 boys) aged 9-11 years, 76% (35) had levels of 25-hydroxyvitamin D (25(OH)D) below 50 nmol/L (20 ng/mL) and 32% had levels below 37 nmol/L (15 ng/mL).