Caffeine has been on doctors’ radars for years. They’ve tried to determine how much coffee intake per day is healthy for you, and how much caffeine might be harmful. Interestingly, multiple studies in recent years have started contradicting earlier research about the benefits of coffee.
Scientists determined a few years ago that drinking three cups of coffee per day might reduce the risk of cardiovascular disease death compared to people who don’t consume any caffeine. However, a new study gives us bad news about coffee intake and heart health.
Researchers from India found that drinking more than four cups of coffee per day, or the equivalent of 400mg of caffeine, raises the risk of cardiovascular conditions like high blood pressure.
The researchers announced their findings at ACC Asia 2024 (via StudyFinds).
“Regular caffeine consumption could disturb the parasympathetic system, leading to elevated blood pressure and heart rates,” lead author Dr. Nency Kagathara said in a statement. “Our study sought to determine the effects of chronic caffeine consumption on heart health, specifically the recovery of heart rate and blood pressure.”
The researchers defined regular caffeine consumption as the intake of caffeinated drinks five days per week for more than a year. They didn’t include just coffee in the study, but also tea and aerated beverages (Coke, Pepsi, Redbull, Sting, and Monster).
Kagathara’s team recruited 92 individuals between 18 and 45 who do not suffer from high blood pressure. Each participant went through three-minute step tests. The researchers measured each individual’s heart rate and blood pressure one minute and five minutes after the test. They also recorded sociodemographic data and caffeine intake habits for each volunteer.
After assessing the data, the researchers found that 19.6% of the participants consumed more than 400 mg of caffeine daily. That’s four cups of coffee, two energy drinks, or ten cans of soda.
Consuming more than 400 mg of caffeine will impact the autonomic nervous system, which is responsible for body functions including heart rate and blood pressure. As such, prolonged intake of more than four cups of coffee per day can lead to elevated heart rates and blood pressure.
The researchers found that the volunteers who consumed more than 600mg of caffeine daily had “significantly elevated” heart rates and blood pressure after five minutes of rest following the exercise.
The study also showed that specific groups had the highest daily caffeine intake. Participants who were female, employed in business and management roles, and lived in urban areas were more likely to consume more caffeine.
Developing high blood pressure is a health risk in itself. Hypertension increases the risk of other heart issues, including coronary artery disease and heart failure. Other risks associated with high blood pressure include chronic kidney disease and dementia.
The researchers point out other factors that can impact blood pressure besides coffee. Alcohol use, smoking, age, genetics, and salt consumption can all contribute to high blood pressure. Lifestyle changes, like increasing physical activity and choosing a nutritious diet, can reduce the risk of high blood pressure.
As someone who drinks at least four cups of coffee daily, I pay attention to studies like this one. I don’t have any heart issues right now, but I started running marathons to delay the risk of heart issues. I can’t wait for Apple to add blood pressure readings to the Apple Watch so I can hopefully catch the signs of high blood pressure early.
