After examining 25,000 middle age men and women, researchers noticed that those who drank the least and the most coffee exhibited the greatest risk of coronary artery calcium – a distinctive sign that arteries are about to clog, which causes heart disease.
The effect of coffee consumption on heart health has been debated over a long time, and studies have reached opposing conclusions.
For a long time, research indicated that coffee may lead to heart disease, as it raises blood pressure and cholesterol.
A recent meta-analysis of 356 studies however, suggested that drinking coffee in moderation may, in fact, protect the heart.
The research was published in the journal Heart.
The study concludes that three to five cups of coffee a day is the optimum amount to drink for protecting the heart.
The international study, led by the Kangbuk Samsung Hospital, Seoul, screened thousands of patients for the presence of coronary artery calcium – an early sign of clogged arteries, which can harden and narrow, leading to clots which can trigger heart attacks. The group, who had an average age of 41, and no signs of strokes, were also asked detailed questions about their eating and drinking habits.
Researchers created five categories for coffee consumption as none, less than one cup a day, one to three cups a day, three to five per day, and more than five cups per day.
The study found that people drinking between three to five cups of coffee a day had the lowest amount of coronary artery calcium (CAC), followed by those who drank between one to three cups a day.
Participants who drank less than one cup a day and those who drank at least five cups of coffee had the highest level of calcium.
Coffee consumption is already linked with improved insulin sensitivity, which leads to a reduced risk of type 2 diabetes.
The authors conclude: “Our study adds to a growing body of evidence suggesting that coffee consumption might be inversely associated with CVD [cardiovascular disease] risk. Further research is warranted to confirm our findings and establish the biological basis of coffee’s potential preventive effects on coronary artery disease.”