AlgaeCal is the only plant calcium supplement certified organic by USDA. AlgaeCal contains many trace minerals and ample Vitamin D3 (which is mandatory to get calcium to the bones), and increases your bone density. According to clinical studies, people who took AlgaeCal products with 1600 IU per day increased their bone density by over 2 % within a year. AlgaeCal compared to traditional calcium supplements is as different as plant compared to rock. You must increase your bone density if you want to decrease your chance of fractures. And AlgaeCal is the only calcium product that is proven to do that.