According to research presented at the American College of Cardiology’s 71 Annual Scientific Sessions, coffee intake (especially two to three cups per day) is associated with lower heart disease risk and dangerous heart rhythms. It also increases longevity. These trends were true for both those with and without heart disease. Researchers concluded that the largest analysis of coffee’s role in death and heart disease, which was done by researchers from a variety of countries, provided reassurance to coffee drinkers that it isn’t linked to any new or worsening diseases and may be actually heart protective.
Peter M. Kistler, MD, professor and head of arrhythmia research at the Alfred Hospital and Baker Heart Institute in Melbourne, Australia, and the study’s senior author said “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. We found coffee drinking had either a neutral effect—meaning that it did no harm—or was associated with benefits to heart health.”
Kistler and his colleagues used data from the UK BioBank. This large prospective database contains health information from more than half a million people, who had been followed for at least 10 years. Researchers examined coffee consumption levels, which could range from a cup to six cups per day, and their relationship to heart rhythm problems (arrhythmias). They also looked at cardiovascular disease including heart failure, stroke, and total and heart-related deaths in people with and without cardiovascular disease. The following groups were created: 0-1, 2-3, 4-5 and 5-7, respectively. The questionnaires that were completed at entry to the registry assessed coffee drinking. They found that there was no significant effect on cardiovascular risk, and in some cases, significant reductions in the risk, after accounting for high blood pressure, exercise, smoking, diabetes, and other factors that may also have an impact on heart health and longevity.
Researchers examined data from 382,535 people without heart disease. This was the first study to examine whether coffee consumption played any role in stroke or heart disease. The average age of the participants was 57, with half being women. The greatest benefit was found to be having between two and three cups of coffee per day. This translated to a 10%-15% reduced risk of developing heart disease, heart failure, or any other type of heart problem. People who only drank one cup per day had a lower risk of suffering a stroke or other heart-related deaths. Researchers found a U-shaped relationship between coffee intake and the development of new heart rhythm problems. People who drank two to three cups per day of coffee saw the greatest benefit, with less benefit for those who drank more.
The second study involved 34,279 people who had at least one form of cardiovascular disease. A lower risk of death was found when coffee intake was increased to two to three cups per day. Kistler stated that any amount of coffee did not increase the risk of developing heart rhythm problems such as atrial fibrillation (AFib), or atrial flutter. Drinking coffee was associated with a lower chance of death among the 24,111 individuals included in the analysis. People with AFib who consumed one cup of coffee per day were almost 20% less likely than those who did not drink coffee.
Kistler stated that doctors are often concerned about patients with arrhythmias or cardiovascular disease drinking coffee. They advise them to quit because it could trigger dangerous heart rhythms. Our study showed that regular coffee consumption is safe and could be part a healthy diet for those with heart disease.
Kistler stated that while two to three cups of coffee per day seems to be the best, people should not increase their coffee intake if they feel anxious or uncomfortable.
He said that coffee has many mechanisms that may lower mortality and improve cardiovascular health. Coffee drinkers should be reassured that coffee can still be enjoyed even if they have cardiovascular disease. Coffee is the most popular cognitive enhancer. It wakes you up and makes your mind sharper.
How can coffee beans be good for the heart? Coffee beans contain over 100 bioactive compounds. People tend to associate coffee with caffeine. Kistler stated that these substances can reduce oxidative stress, inflammation, insulin sensitivity, increase metabolism, block certain receptors associated with abnormal heart rhythms and inhibit gut fat absorption.
Researchers looked into whether coffee consumption and cardiovascular disease were affected by whether people drank instant, ground or caffeinated coffee. Researchers found that two to three cups of coffee per day was associated with the lowest risk for arrhythmias and blockages in the heart’s vessels, stroke, heart failure, and even death, regardless of whether the person drank instant or ground coffee. All types of coffee had lower death rates. Decaff coffee had no beneficial effects on incident arrhythmia, but it did decrease cardiovascular disease with the exception of heart attack. Kistler stated that the results suggest that caffeinated coffee is preferred across the board and that decaf coffee has no cardiovascular benefits.
These studies have several limitations. Researchers could not control for diet factors that might play a role for cardiovascular disease. They also couldn’t adjust for creamers, milk, or sugar. The majority of participants were white so further studies are required to see if these findings can be extended to other groups. The study’s coffee intake was determined by participants’ self-reports via a questionnaire at entry. Kistler said that this should be taken into account when interpreting the findings of the study. However, Kistler pointed out that studies have shown that people’s dietary habits do not change over time or in adulthood. Kistler stated that the results should be confirmed in randomised trials.