I think that there is so many products out there that it just comes down to personal preference; although i am sure some are better than others. you just have to find the right balance for yourself between cost and effectivness. personally i have been using a newer calcium product on the market Algaecal which is not a calcium carbonate and comes with 800 IU of natural Vitamin D3 which is needed for absorbsion. I have been feeling really good actually, probably stick with this one for a while. was using the okinawa japan previous which is good too. they do have a website with loads of good info too if you are interested in checking it out.
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