For breastfeeding mommies, it's recommended to take calcium supplements that are combined with magnesium to allow for adequate assimilation into the body. You can try Blackmores Pregnancy and Breastfeeding Advanced -- it contains ample calcium and magnesium, along with other vitamins and minerals beneficial for breastfeeding mommies. Blackmores, to me, is a very reputable brand and I've taken other vitamins and supplements by them and I have no complaints at all. Plus, Blackmores supplements are easily available in major pharmacies like Watsons, Guardian etc, retailing at around $36/-. http://www.watsons.com.sg/Product-Categories/Health/Health-supplements/Vitamins-%26-general-supplements/Pregnancy-%26-Breastfeeding-Advanced-60'S/p/BP_37334