They studied 24,000 German and European patients ages 35-64. Using questionnaires, they quizzed them about their vitamin and mineral supplements. They also tracked their health for 11 years, looking at heart attacks, strokes and death. (These studies can be easily done in countries with Socialized Medicine because everyone has health coverage and electronic records!!!)
They found that the intake of calcium supplements did not affect the risk of stroke, either protection or causation. But the people who took calcium supplements daily were 86% more likely to have a heart attack than those who didn't use any supplements. Dietary calcium caused no problem, it was just the supplements.
What should we make of this study? Dietary calcium is a good thing and calcium from food actually lowered the risk of heart attack. So eating foods with calcium is just fine. But we have relied too much on supplements that are increasingly being found to be worthless in preventing disease and even harmful when taken in large doses.
The average person should not take calcium supplements. They can increase the risk of kidney stones, cause gastrointestinal problems and even heart attacks. It is now becoming clear that recommending vitamin supplements can be harmful and they do not replace good, balanced diets.
Foods with calcium:
low fat dairy, yogurt, cheese, collards, spinach, potatoes, soybeans, turnips