CALCIUM
I take no calcium. It is hazardous for most people, including women. Excess calcium leads to calcification of the heart and arteries, increasing the risk of heart disease 50%. High doses of vitamin K activate decalcification enzymes to remove those harmful deposits (ref). Higher calcium intake is likely to increase the risk for diabetes.
THE KEY to preventing osteoporosis is exercise. By 2020, half of Americans over 50 will be at risk for osteoporosis. A report by the Surgeon General suggests simple steps like getting 30 min of exercise per day will maintain bone health. -Bone Health and Osteoporosis: A Report of the Surgeon General; October, 2004. Note that osteoporosis is rare in nations in Africa or in India, where people get lots of exercise.