A new study has warned that drinking four or more cups of coffee a day could increase the risk of a heart attack or stroke. Researchers have found that more than 400 milligrams of caffeine per day may increase the risk of cardiovascular disease.
Turkish coffee. istock PHOTO
About one in five participants in an Indian study, according to aol.co.uk, consumed at least 400 milligrams of caffeine each day, which translates into about four cups of coffee, 10 boxes of biscuits or two energy drinks.
The research suggested that such “chronic” caffeine consumption could have a significant impact on the autonomic nervous system, increasing heart rate and blood pressure over time.
High blood pressure is associated with an increased risk of coronary heart disease, heart failure, chronic kidney disease and dementia.
High blood pressure weakens the heart over time and is a major risk factor for heart disease.
Tea and coffee, both of which contain caffeine, are an integral part of the morning routine for people around the world, but scientists say they can be “harmful” when consumed in excess.
When you are classified as a heavy coffee drinker
Lead study author Nancy Kagathara of Zydus Medical College and Hospital in Dahod, India, says: “Regular caffeine consumption could disrupt the parasympathetic system, leading to increased blood pressure and heart rate“.
“Our study sought to determine the effects of chronic caffeine consumption on heart health, specifically heart rate and blood pressure recovery“, she says.
Chronic caffeine consumption was defined as the intake of any caffeinated beverages for five days per week for more than one year.
The study focused on tea, coffee and fizzy drinks such as Coca-Cola, Pepsi, Redbull, Monster and Sting.
The research team evaluated a group of 92 healthy people between the ages of 18 and 45. All participants had their blood pressure and pulse measured and underwent a three-minute test.
Blood pressure and heart rate were measured 60 seconds and five minutes after the test. Each participant’s daily caffeine intake was also recorded.
The findings showed that the highest daily caffeine intakes were seen in participants who were female, employed in business and management roles, and lived in urban areas.
Those who consumed the highest amounts, chronic caffeine users of more than 600 mg of caffeine per day, had “significantly” increased heart rates and blood pressure after five minutes of rest following the step test.
Mrs. Kagathara continues: “Because of its effect on the autonomic nervous system, regular caffeine consumption could put otherwise healthy people at risk for high blood pressure and other cardiovascular events. Increasing awareness of these risks is vital to improving heart health for all“.
Other factors that may contribute to high blood pressure include alcohol consumption, smoking, age, family medical history, and salt intake.
But increasing physical activity, eating a nutritious diet, and other lifestyle changes could help lower blood pressure and reduce the risk of heart disease.
The findings of the new study are to be presented at the American College of Cardiology (ACC) Asia 2024 conference in Delhi, India, and as such should be considered preliminary until publication in a peer-reviewed journal.
How much coffee is safe to drink?
While there are plenty of perceived benefits of coffee, experts are also keen to point out that it is not a ‘magic bullet’ and should be enjoyed in moderation.
“It is important to recognize that, when consumed in moderation, coffee may provide certain health benefits due to its antioxidant properties and potential to improve mental alertness”, explains Dr. Joseph Ambani. “However, as with many things, moderation is key.
“Caffeine is a stimulant that can increase blood pressure and heart rate, which over time can contribute to heart problems, especially in people with pre-existing conditions such as high blood pressure or arrhythmias”, continues Dr Ambani.
What the authorities say in the field
According to the European Food Safety Authority’s (EFSA) review of Caffeine Safety, safe coffee consumption can be defined as three to five cups a day, up to 400mg per day, while the NHS says more than 600 mg/day may cause anxiety, insomnia, restlessness, palpitations, diarrhea, and restlessness.
It’s also worth considering the size of the cup of coffee you’re drinking and the type. According to Coffee Code UK, there are a number of things that affect how much caffeine there is in a cup of coffee, including the type of coffee used, the brewing method and the level of roast, but as a guide they anticipate it to be between 63mg. at 100 mg in a single cup, more in a larger cup.
Also remember that caffeine is not only found in coffee, but also in tea, fizzy drinks, chocolate and certain energy drinks, so remember to monitor your total intake.
“For most people, drinking one to three cups of coffee a day is generally considered safe and may even be beneficial”, continues Dr Ambani.
“However, I often advise my patients to be careful about their overall caffeine intake, which includes not only coffee, but also tea, energy drinks, and certain medications. The safe upper limit is usually around 400 milligrams of caffeine per day, which equates to about four cups of brewed coffee, but individual tolerance can vary significantly.”
Some people are more sensitive to caffeine and can experience adverse effects even at lower levels of consumption, says the specialist. Symptoms such as palpitations, anxiety and insomnia can be early indicators that caffeine intake should be reduced.
“Although moderate coffee consumption is generally safe for most people, it’s essential to listen to your body and adjust your intake based on your health and how you personally react to caffeine”, continues Dr Ambani.
“For those with underlying heart conditions or those who are particularly sensitive to caffeine, I would recommend limiting coffee to one or two cups a day or drinking decaffeinated coffee“.
