References :
1.Nordin BE. The effect of calcium supplementation on bone loss in 32 controlled trials in postmenopausal women. Osteoporos Int. 2009 Dec;20(12):2135-43. http://www.ncbi.nlm.nih.gov/pubmed/19459026
2.Institute of Medicine. Food and Nutrition Board. Comprehensive DRI tables for vitamins, minerals and macronutrients; organized by age and gender. Includes the 2010/2011 updated recommendations for calcium and vitamin D. Click the following links: http://www.iom.edu/Activities/Nutrition/SummaryDRIs/~/media/Files/Activity%20Files/Nutrition/DRIs/5_Summary%20Table%20Tables%201-4.pdf Or http://www.iom.edu/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/DRI-Values.aspx