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Calcium Supplements are Bad for the Heart

"One, I am skeptical of the effectiveness of nutritional supplements."
- Michael Shermer

The May 23, 2012 issue of the journal HEART includes a publication which casts an enormous shadow of doubt on calcium supplements.

Australian authors Ian Reid and Mark J Bolland report:

"Calcium is a micronutrient widely believed to affect bone heath, though the importance of normal variations in calcium intake may have been overemphasised."

"The safety of calcium supplements is now coming under considerable scrutiny."

"Their use in osteoporosis had caused concern with respect to the risk of renal calculi, which is increased by about 20%."

There has also been a longstanding awareness that they cause gastrointestinal symptoms, particularly constipation, but it is more alarming to find that they double the risk of admission to hospital with an acute abdominal condition."

"The concern that most threatens their continuing use, however, is their potential risk to cardio- vascular health." "This concern first surfaced in nephrology practice with evidence that calcium supplements exacerbated vascular calcification and contributed to the very high cardiovascular mortality experienced by those patients."

Eleven major clinical experiments were analyzed, and researchers found:

"A 31% increase in risk of myocardial infarction, which was statistically significant."

Reid and Bolland write:

"Recent data from a randomised, controlled trial in Australia are sobering. Six hundred and two elderly, frail individuals were randomised to control, daily sunshine exposure, or daily sunshine exposure plus calcium 600 mg/day. Follow-up extended to almost 3 years, during which time there were 218 deaths. Comparisons between the sunshine and sunshine plus calcium groups showed a 47% increase in total mortality and a 76% increase in cardiovascular mortality associated with randomisation to the calcium supplements." Authors conclude:

"Thus, the evidence is steadily mounting for a real cardiovascular adverse effect from the use of calcium supplements, raising the question as to whether this is large enough to abrogate the beneficial effects on fractures. In fact, the anti-fracture effects of calcium are modest, having been demonstrated in only two studies of calcium plus vitamin D, and suggested to be of the order of about 10% reduction, in meta-analyses."

Their final comment:

"It is now becoming clear that taking this micronutrient in one or two daily boluses is not natural, in that it does not reproduce the same metabolic effects as calcium in food."

NOTMILKMAN'S NOTE: Calcium taken in cow's milk is poorly absorbed. In order to absorb one milligram of calcium one needs an equal milligram of magnesium. Magnesium is the center atom of chlorophyll. A 100-gram portion of cow's milk contains 118 milligrams of calcium and only 18 milligrams of magnesium. What happens to the unused 100 milligrams of calcium? Read this column again, and you'll see that cow's milk for humans is actually a dangerous calcium supplement.

* A 100-gram portion of cooked broccoli contains 40 milligrams of calcium and 21 milligrams of magnesium.

** A 100-gram portion of (unfortified) soymilk contains 25 milligrams of calcium and 25 milligrams of magnesium.

*** A 100-gram portion of whole cow's milk contains 118 milligrams of calcium and 18 milligrams of magnesium.

Do the math.

Robert Cohen

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