WASHINGTON — Coffee drinkers, rejoice! Drinking two or three cups a day could add years to your life by keeping your heart healthy. Researchers found that the world’s most popular beverage lowers the risk of heart disease and dangerous heart rhythms — helping people live longer.
The study reveals this benefit applies to both healthy individuals and those with cardiovascular disease. In the biggest analysis of its kind, scientists tracked more than 400,000 people from the United Kingdom for at least a decade.
“Because coffee can quicken heart rate, some people worry that drinking it could trigger or worsen certain heart issues. This is where general medical advice to stop drinking coffee may come from. But our data suggest that daily coffee intake shouldn’t be discouraged, but rather included as a part of a healthy diet for people with and without heart disease,” says senior author Professor Peter Kistler of the Baker Heart Institute in Melbourne, Australia, in a media release.
“We found coffee drinking had either a neutral effect—meaning that it did no harm—or was associated with benefits to heart health.”
Drinking more coffee won’t provide extra benefits
The team found that the optimum effects of drinking coffee appeared in people who had two or three cups each day. They had a 10 to 15-percent lower risk of developing coronary heart disease, heart failure, a heart rhythm problem, or dying for any reason.
That benefit is in comparison to adults who never touch coffee during the day. Researchers note that coffee beans have over 100 nutritious plant chemicals in them. They dampen oxidative stress and inflammation and improve insulin sensitivity and metabolism, Prof. Kistler explains.
The biologically active compounds also block absorption of fat into the gut and molecules linked to abnormal heart rhythms. Overall, participants consuming less than two cups, or more than three cups did not fare as well as those in the two-to-three-cup range.
However, the risk of stroke or heart-related death was lowest among those who drank one cup of coffee a day. Drinking coffee also had a connection to a lower risk of death for people among people diagnosed with an arrhythmia — an irregular heartbeat.
For example, those with AFib (atrial fibrillation) were nearly 20 percent less likely to die than non-coffee drinkers if they had one cup a day.
“Clinicians generally have some apprehension about people with known cardiovascular disease or arrhythmias continuing to drink coffee, so they often err on the side of caution and advise them to stop drinking it altogether due to fears that it may trigger dangerous heart rhythms,” Kistler says. “But our study shows that regular coffee intake is safe and could be part of a healthy diet for people with heart disease.”
‘Coffee drinkers should feel reassured’
Study authors caution that people shouldn’t increase their coffee intake if it makes them feel anxious or uncomfortable. However, the new findings provide reassurance that coffee isn’t tied to new or worsening heart disease — and may actually be heart protective.
“There is a whole range of mechanisms through which coffee may reduce mortality and have these favorable effects on cardiovascular disease,” the study author adds.
“Coffee drinkers should feel reassured that they can continue to enjoy coffee even if they have heart disease. Coffee is the most common cognitive enhancer—it wakes you up, makes you mentally sharper and it’s a very important component of many people’s daily lives.”
The international team used data from the UK BioBank – looking at consumption ranging from up to a cup to more than six cups of coffee a day. They compared levels with heart rhythm problems (arrhythmias), cardiovascular disease, and both total and heart-related deaths. In many cases, coffee significantly reduced risks to heart health, regardless of exercise, alcohol, smoking, diabetes, and high blood pressure.
Decaf not as beneficial as regular coffee
The researchers followed 382,535 men and women with an average age of 57 without known heart disease. Secondly, they included 34,279 individuals who had some form of cardiovascular illness at the outset. Among these individuals, drinking two to three cups a day had a link to lower odds of dying compared to people who never drink coffee.
Importantly, consuming any amount of coffee did not increase the risk of heart rhythm problems including AFib or atrial flutter. This is often what clinicians are concerned about, Prof. Kistler notes.
Of the 24,111 people included in the analysis who had an arrhythmia, drinking coffee lowered their risk of death. For example, people with AFib who drank one cup of coffee a day were nearly 20 percent less likely to die than non-coffee drinkers.
A third analysis of instant, ground, caffeinated or decaf coffee again found two to three daily cups was best. Death rates dropped among all participants.
Decaf did not have favorable effects against arrhythmia cases but reduced cardiovascular disease — with the exception of heart failure. This suggests caffeinated coffee is preferable across the board and there are no benefits to choosing decaf over caffeinated coffees, according to the researchers.
Cardiovascular disease is the world’s number one killer, claiming an estimated 17.9 million lives each year. Previous studies have also found links between drinking coffee and combating cancer, dementia, diabetes, and depression.
The team is scheduled to present their findings at the American College of Cardiology’s 71st Annual Scientific Session.
South West News Service writer Mark Waghorn contributed to this report.