 All subjects will be assigned to receive 1g of calcium carbonate daily. Oral Cholecalciferol powdered will be ingested under direct supervision during study visits. Each dose of Cholecalciferol will be diluted in 10 mls of water. The Cholecalciferol used in this study is formulated as spray dried powder stabilized with DL-alpha tocopherol dry vitamin D3 100 SDSDSM Nutritional Products Switzerland Ltd. 