Whenever we read research backing up our coffee-drinking habits, we’re eager to publish it. I mean, who doesn’t love coffee? If you don’t have a daily cup, then you may want to change your mind after reading the latest research. The research was published on the 27th of September 2022 in the European Journal of Preventive Cardiology. It concludes that drinking two to three cups of coffee a day is linked with a healthier heart and longer lifespan. It’s also linked to a lower risk of cardiovascular disease compared to avoiding coffee.
The link between coffee, heart disease, and longevity
There’s a growing library of research on the health benefits of coffee. However, according to the researchers of this particular study, “there’s little information on the impact of different coffee preparations on heart health and survival. Therefore, this study examined the associations between types of coffee and incident arrhythmias, cardiovascular disease and death.”
The researchers used data from the UK Biobank, on adults between 40 and 69 years of age. Heart disease, or CV as it is also known, consists of coronary heart disease, congestive heart failure, and ischemic stroke.
What the researchers found
Most of us know that one of coffee’s powerful compounds is caffeine. Even so, coffee is made up of more than 100 different biological agents. The aim of this study was to provide some mechanistic insights into the role of caffeine in cardiovascular (CV) outcomes by comparing the impact of decaffeinated and caffeinated coffee.
“In summary the results suggest that mild to moderate intake of ground, instant and decaffeinated coffee should be considered part of a healthy lifestyle.”
“In this large, observational study, ground, instant, and decaffeinated coffee were associated with equivalent reductions in the incidence of cardiovascular disease and death from cardiovascular disease or any cause,” said study author Professor Peter Kistler.
Professor Kistler is an international leader in cardiac arrhythmia research. He is the Head of Clinical Electrophysiology Research at the Baker Heart and Diabetes Institute and Head of Electrophysiology at The Alfred hospital. He has joint appointments as a Professor of Medicine at the University of Melbourne and Monash University in Australia.
A significant number of participants
The study included 449,563 participants free of arrhythmias and other cardiovascular diseases at baseline. The median age was 58 years and 55.3% were women.
Participants completed a questionnaire asking how many cups of coffee they drank each day. They also had to state whether they usually drank instant, ground (such as cappuccino or filtered coffee), or decaffeinated coffee.
They were then grouped into six daily intake categories, consisting of none, less than one, one, two to three, four to five, and more than five cups per day.
What kind of coffee were the participants drinking?
The usual coffee type was instant in 198,062 (44.1%) participants, ground in 82,575 (18.4%), and decaffeinated in 68,416 (15.2%). There were 100,510 (22.4%) non-coffee drinkers who served as the comparator group.
How coffee works for your heart and lifespan
Coffee drinkers were compared to non-drinkers for the incidence of arrhythmias, heart disease, and death. This was done after adjusting for age, sex, ethnicity, obesity, high blood pressure, diabetes, obstructive sleep apnea, smoking status, and tea and alcohol consumption. Outcome information was obtained from medical records and death records. The median follow-up was 12.5 years. A total of 27,809 (6.2%) participants died during follow-up.
All types of coffee were linked with a reduction in death from any cause.
Reduction of risk
The greatest risk reduction is seen with two to three cups per day. This compared to no coffee drinking was associated with a 14%, 27%, and 11% lower likelihood of death for decaffeinated, ground, and instant preparations, respectively.
What type of coffee matters?
It may surprise you to know that when it comes to what type of coffee, the findings apply to the ground, instant, and decaffeinated varieties. Heart disease was diagnosed in 43,173 (9.6%) participants during follow-up.
All coffee subtypes were associated with a reduction in incident heart disease.
How much is enough?
You may be wondering, though, how many cups a day is optimal. In this particular study, the researchers believe two to three cups a day provide the lowest risk.
“Again, the lowest risk was observed with two to three cups a day, which, compared to abstinence from coffee, was associated with a 6%, 20%, and 9% reduced likelihood of cardiovascular disease for decaffeinated, ground, and instant coffee, respectively.”
Does coffee make your heart beat too fast?
An arrhythmia was diagnosed in 30,100 (6.7%) participants during follow-up. Arrhythmia is a problem with the rate or rhythm of your heartbeat. It means that your heart beats too quickly, too slowly, or with an irregular pattern.
This is not to be confused with tachycardia or bradycardia. When the heart beats faster than normal, it is called tachycardia. When the heart beats too slowly, it is called bradycardia
Ground and instant coffee, though not decaffeinated, were associated with a reduction in arrhythmias, including atrial fibrillation.
Compared with non-drinkers, the lowest risks were observed with four to five cups a day for ground coffee and two to three cups a day for instant coffee, with 17% and 12% reduced risks, respectively.
Yes, coffee enhances your brain function, but beware not to drink too much
Of course, it’s important not to get carried away. Also one naturally assumes that you should not lade your coffee with sugar and milk either.
Excessive coffee drinking can be problematic. Acute caffeine intake results in sympathetic activation, mediated by phosphodiesterase inhibition, cytosolic calcium increase, and stimulation of noradrenaline/adrenaline release. As the researchers explain:
“Coffee is the most common cognitive enhancer, increasing mental alertness and concentration. However, higher intake levels can result in feelings of anxiety, restlessness, insomnia, and psychomotor agitation, with toxic effects estimated to occur with intakes of ≥1.2 g.”
If you drink too much, you can also increase arrhythmia risk particularly, particularly if you have a pacemaker or any other heart condition.
Coffee may acutely elevate blood pressure through sympathetic activation, although tolerance develops quickly and there is minimal effect on long-term blood pressure control.
Caffeine can adversely impact the effects of antihypertensive medications, including beta-blockers and calcium-channel blockers like felodipine.
Why do some people tolerate coffee better than others?
Do you ever wonder why some people you know can drink a cup of coffee any time of the day without it having too much disruptive effect?
Well, again, the researchers explain it like this. “Caffeine has near 100% bioavailability with metabolism determined by cytochrome CYP1A2 enzyme activity, which varies by as much as 24%. Furthermore, CYP1A2 activity can be affected by medications and dietary factors.”
This may explain the considerable variation in the effects and tolerability of coffee between individuals.
Few studies have explored the relationship between the habitual intake of different coffee subtypes, and more specifically the impact of caffeinated vs. decaffeinated coffee, on CV endpoints and mortality. In this study, ground and instant but not decaffeinated coffee consumption was associated with a significantly lower risk of incidental heart arrhythmias.
Heart rate variability and coffee
The researchers also commented that “habitual coffee consumption has not been shown to result in changes in heart rate, electrocardiogram parameters, or heart rate variability. Caffeine also has antiarrhythmic properties, particularly through the inhibition of adenosine A1 and A2A receptors. Endogenous adenosine shortens refractory periods in both the atrium and ventricle and, consequently, increases the risk of arrhythmias. By blocking adenosine receptors, caffeinated coffee may mitigate the effects of endogenous adenosine and protect against arrhythmias. This may explain the differing effects of caffeinated vs. decaffeinated coffee on the incidence of arrhythmias reported in the present study.”
Arrhythmia reduction was seen with caffeinated, but not decaffeinated coffee.
In summary, the researchers then believe mild-moderate coffee intake of all types should not be discouraged, but rather considered part of a healthy lifestyle. Decaffeinated, ground, and instant coffee, particularly at 2–3 cups/day, were associated with significant reductions in incident CVD and mortality. Ground and instant, but not decaffeinated coffee, was associated with reduced heart arrhythmia.
Professor Kistler said: “Caffeine is the most well-known constituent in coffee, but the beverage contains more than 100 biologically active components. It is likely that the non-caffeinated compounds were responsible for the positive relationships observed between coffee drinking, cardiovascular disease and survival. Our findings indicate that drinking modest amounts of coffee of all types should not be discouraged but can be enjoyed as a heart healthy behaviour.”
Thanks to Crystal Shaw on Unsplash. for the inspirational main image of a woman drinking coffee.
Comments for this article were supplied by the media resource of the European Society of Cardiology.
The ESC brings together health care professionals from more than 150 countries, working to advance cardiovascular medicine and help people to live longer, healthier lives. You can follow them on Twitter @ESCardioNews
1Chieng D, Canovas R, Segan L, et al. The impact of coffee subtypes on incident cardiovascular disease, arrhythmias, and mortality: long-term outcomes from the UK Biobank. Eur J Prev Cardiol. 2022. doi:10.1093/eurjpc/zwac189.