In the Dutch study, coronary calcification was detected with the use of electron beam computed tomography, and a severe rating was defined as an Agatson calcium score of >400. Coronary calcification in women was significantly reduced for those who consumed three to four cups of coffee and also for those who drank more than four cups of coffee per day. This reduction remained even when the women consumed additional caffeinated beverages like tea, but the association was not modified by smoking.

Calcium calcification is a distinct marker to indicate a diseased artery. It is estimated that patients who die of coronary artery disease (the #1 killer in the US) have two to five times as much calcium in their arteries as those who die of other causes. Coronary calcification is not necessarily an older person's condition, and many reports indicate that it can start to develop in people as young as 10 to 20-years-old.

The calcification is actually calcium phosphate (hydroxyapatite), which is similar to that in bone. Today, scientists believe the calcification process is due to, perhaps, a response to injury, not unlike bone mineralization. The extent of coronary atherosclerosis (total calcium score) is the most powerful predictor of subsequent or recurrent cardiac events. And, while heart attacks do occur in patients with low calcium scores, the incidence is low, according to reports by the American Heart Association. Making this whole topic a challenge is determining how calcium deposits in atherosclertoic plaque is formed; the answer remains unclear.

The Dutch researchers engaged 1,570 older Dutch men and women subjects, free from heart disease, both smokers and nonsmokers, and studied how coffee intake could or could not relate to the development of severe coronary calcification. Among men who smoked, there was a non-significant inverse relationship, however, in nonsmoking men a direct association was observed.

Among the many factors in the analysis were adjustments for age, smoking, BMI (body mass index), education and intake of energy and alcohol. The study recommended additional research to clarify possible effect modification by gender and smoking.