The data is not so strong as to suggest that nobody should take calcium supplements. It is true that if you have higher calcium levels you are more likely to develop hard atherosclerotic plaques. This study also suggests that when people start taking calcium they have an increase in MI's that must be due to increased calcium levels in the blood, not atherosclerosis. In general you need to manage your cardiovascular risk in about 100 ways. The best time to take calcium so that you integrate it into bone is at bedtime. I'm sure there will be more to know about this......and this info needs to be taken in the greater context.