Drinking a few cups of coffee a day may help people avoid clogged arteries - a known risk factor for heart disease. Researchers in Korean believe.
A studied of more than 25,000 male and female employees who received routine health checks at their place of work.
Employees who drank a moderate amount of coffee, three to five cups a day, were less likely to have early signs of heart disease on their medical scans.
The findings reopen the debate about whether coffee is good for the heart or not.
Some studies have linked consumption to heart risk factors, such as raised cholesterol or blood pressure, while others suggest the beverage may offer some heart protection.
None of the employees included in the Korean study had outward signs of heart disease, but more than one in 10 of them were found to have visible calcium deposits on their scans.
The researchers then compared the scan results with the employees' self-reported daily coffee consumption, while taking into account other potential heart risk factors such as smoking, exercise and family history of heart problems.
People who drank a few cups of coffee a day were less likely to have calcium deposits in their coronary arteries than people who drank more than this or no coffee at all.
The study authors say more research is needed to confirm and explain the link.
Coffee contains the stimulant caffeine, as well as numerous other compounds, but it's not clear if these might cause good or harm to the body.
Victoria Taylor of the British Heart Foundation said: "While this study does highlight a potential link between coffee consumption and lower risk of developing clogged arteries, more research is needed to confirm these findings and understand what the reason is for the association.
Care is needed when generalizing study results because it is based on the South Korean population, who have different diet and lifestyle habits to people in different parts of the world.