People who drink three to five cups of coffee a day are less likely to develop clogged arteries that could lead to heart attacks, a study has found.
An international team of researchers, led by the Kangbuk Samsung hospital in Seoul, South Korea, found that people who consume a moderate amount of coffee had the least risk of coronary calcium in their arteries.
Coronary artery calcium (CAC) is an early indicator of coronary atherosclerosis, a hardening and narrowing of the arteries, which can cause blood clots that can trigger a heart attack or stroke.
Previously concerns had been expressed about a potential increase in heart disease risk associated with drinking coffee, which has been linked to increased cholesterol concentrations and heightened blood pressure. But the authors of the paper, published in the journal Heart on Monday, said their findings chimed with a recent meta-analysis of 36 studies that showed moderate coffee consumption was associated with a decreased risk of heart disease.
They said: “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.”
The British Heart Foundation (BHF) agreed that more work was needed and warned about generalising results garnered from studying research based on the South Korean population to people with different lifestyles and diets.
Researchers examined a group of 25,138 men and women in South Korea, with an average age of 41, who had no signs of heart disease, attending a health-screening examination.
They estimated the CAC score ratios associated with different levels of coffee consumption compared with no coffee consumption, taking into account other factors such as level of education and physical activity, alcohol and cigarette consumption, BMI (body mass index), family history of heart disease and diet.
The ratio was 0.59 for those consuming three to five cups per day, compared with non-coffee drinkers. For those drinking less than one cup a day it was 0.77, falling to 0.66 for people having one to three cups. The ratio rose to 0.81 for people having five or more a day.
The association was similar in subgroups defined by age, sex, smoking status, alcohol consumption, status of obesity, diabetes, hypertension, and hypercholesterolaemia.
A possible explanation is that chronic coffee consumption has a possible link to reduced risk of type 2 diabetes, a strong risk factor for atherosclerosis, the authors suggested. They also said that coffee drinking might improve insulin sensitivity and the function of Î²-cells, which store and release insulin.
Victoria Taylor, the BHF senior dietician, 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.
“We need to take care when generalising these results because it is based on the South Korean population, who have different diet and lifestyle habits to people in the UK.”