Do you really need calcium? 12. August 2009 William Davis (0) Why are we advised to take calcium supplements?Men and women are advised to take calcium because it has been shown to reduce blood pressure modestly. Women, in particular, can stall the deterioration of bone strength (mineralization) by taking calcium supplements, 1200-1300 mg per day, and eating calcium-rich foods like dairy products. Is that all true?It is true insofar as we remain vitamin D deficient. A funny thing happens when you fully replete vitamin D: Intestinal absorption of calcium as much as quadruples. That means your body will efficiently absorb the calcium in broccoli and spinach. Is it still necessary to force-feed your body megadoses of calcium once vitamin D has been repleted? I don’t think so. While the evidence is indirect, several observations point towards the lack of necessity of calcium once vitamin D is addressed. For instance:Women who take calcium, 1200 mg per day, with vitamin D, 800 units per day, double their five-year risk for heart attack, according to a New Zealand study. Men who take calcium, 1200 mg per day, with vitamin D, 800 units per day, also may substantially increase heart attack risk. Bone density increases more with vitamin D than with calcium. Calcium may not even be necessary to increase bone mineralization, since there are data to suggest that vitamin D can accomplish this by itself. Calcium suppresses parathyroid hormone, PTH. That is, in fact, how calcium stalls (usually does not reverse) bone mineral loss-not by adding calcium to bone, but by suppressing PTH release. (PTH causes bone demineralization.) Vitamin D suppresses PTH to a far greater degree than calcium.What is needed is a broad reconsideration of the advice everyone is getting to take calcium. In an age when more and more people are appreciating the power of vitamin D supplementation to achieve normal blood levels, there may be danger ahead for those who fail to address their calcium overdosing.