The Prevalence of Vitamin D Insufficiency in Primary School Children and Comparison of the Effect of Calcium-Vitamin D-Fortified Milk, -Orange Juice and Calcium-Vitamin D Supplement

At the first step, serum 25-(OH)D, PTH(parathyroid hormone), osteocalcin, bone alkaline phosphatase, calcium, phosphorous, and magnesium is evaluated. Anthropometric and dietary intake data is also collected. In the second phase, we have 6 experimental groups: (1) plain milk; (2) calcium-vitamin D-fortified milk (containing 500 mg Ca and 100 IU vitamin D/200 mL package); (3) plain orange juice; (4) fortified orange juice containing equal amounts of calcium and vitamin D as fortified milk; (5) calcium-vitamin D supplement (500 mg calcium and 200 IU vitamin D); and (6) placebo. Each group consists of 40-60 children (9-11 years) from both sexes. All above-mentioned biochemical, anthropometric and dietary intake data is collected both in the beginning and in the end of interventional period.