Drinking This Many Cups of Coffee Each Day Could Put Your Heart Health at Risk

Fast Fact

• New research found that consistently drinking more than 400 milligrams of caffeine each day could put a person at a higher risk of cardiovascular issues.
• The FDA recommends that people drink no more than 400 milligrams of caffeine daily, which amounts of about four cups of coffee, two energy drinks, or 10 cans of soda.
• Research on caffeine consumption is mixed, but there’s some evidence that it can raise a person’s heart rate and blood pressure.

There’s nothing like a dose of caffeine on a groggy morning to give you a much-needed boost of energy—but new research suggests drinking too much caffeine could be bad news for your heart health. In the U.S., it’s estimated that about 85% of people drink at least one caffeinated beverage a day. Whether you prefer coffee, tea, soda, or energy drinks, the Food and Drug Administration (FDA) recommends that healthy people consume no more than 400 milligrams (mg) of caffeine each day.

However, consistently meeting or exceeding this threshold could be harmful to your body, according to new research. A study found that people who consumed more than 400 mg of caffeine most days had a higher risk of cardiovascular disease, despite being healthy.bAmerican College of Cardiology. New study finds chronic high caffeine consumption may heighten risk for cardiovascular disease.

Participants who drank this much caffeine frequently were more likely to have elevated heart rates and blood pressure over time, raising the risk of heart health issues. “In general, chronic elevations of blood pressure are a risk factor for future cardiovascular disease such as heart attack, heart failure, or stroke,” Jason Hopper, MD, a cardiologist at Norton Heart & Vascular Institute, told Health.

Here’s what experts had to say about the new research, how caffeine can affect your cardiovascular system, and which caffeinated drinks you should choose to best protect your health.

Drinking Too Much Caffeine Could Put Stress on Your Cardiovascular System

The researchers analyzed a group of 92 healthy people who were between 18 and 45 years old, all of whom had normal blood pressure. Participants had their blood pressure and pulse measured, then were asked to do a three-minute step test—this evaluates a person’s cardiovascular capacity based on how their heart rate slows during a recovery period.

In addition, the researchers also documented how much caffeine from tea, coffee, and carbonated drinks such as Coke, Redbull, and Monster, each participant consumed daily. American College of Cardiology. New study finds chronic high caffeine consumption may heighten risk for cardiovascular disease.

Nearly 20% of participants had at least 400 mg of caffeine each day, which is equivalent to drinking four cups of coffee, two energy drinks, or 10 cans of soda. Consuming this much caffeine was shown to significantly impact participants’ autonomic nervous system, raising their heart rates and blood pressure over time.

The results were even more serious among those who consistently drank more than 600 mg of caffeine in one day; in the five minutes of rest following the step test, these participants had significantly elevated heart rates (100 beats per minute) and blood pressure (140/90 mm Hg, where 120/80 mm Hg is normal). “Due to its effect on the autonomic nervous system, regular caffeine consumption could put otherwise healthy individuals at risk of hypertension and other cardiovascular events,” Nency Kagathara, MBBS, research author and researcher at the Zydus Medical College and Hospital in India, said in a press release. “Increasing awareness of these risks is vital to improve heart health for all.”

How Can Caffeine Affect Your Heart Health?

The relationship between caffeine and the cardiovascular system is well-established. For one, caffeine is known as a vasoconstrictor, which means that it can narrow the blood vessels and raise blood pressure. “When the blood vessels become more narrow with the same amount of blood moving through them, the pressure increases. This is similar to the same volume of water flowing through a hose versus through a straw,” Amber Core, RD, a registered dietitian at The Ohio State University Wexner Medical Center, told Health. Elevated blood pressure increases the workload on the heart, which can sometimes lead to heart failure and abnormal heart rhythms in the long run, she added. Caffeine is also a stimulant, so it tells the brain to be on alert—this triggers the body’s fight or flight response in the autonomic nervous system, which is responsible for regulating heart rate, blood pressure, and more.

“As a part of this response, heart rate will often increase as the body prepares for any potential danger or threat,” Core said. However, these elevations in blood pressure and heart rate are usually seen in the short term after a person consumes caffeine, and are less profound among chronic caffeine drinkers, said Hopper. “The body can adapt to regular caffeine consumption, so these changes are more noticeable in people who don’t consume caffeine habitually,” he said.

Still, research on the consumption of coffee, tea, and other caffeinated drinks is mixed. One study suggested that moderate coffee consumption leads to a decrease in all-cause and cardiovascular-related mortality, hypertension, cholesterol, heart failure, and atrial fibrillation. Drinking coffee has also been linked to a lower risk of type 2 diabetes and could protect against dementia, among other benefits.

But other research has found drinking more than two cups of coffee every day could increase risk of dying from cardiovascular disease, specifically for people with very severe hypertension. People may also experience a fast heart rate, jitters, tremors, or heart palpitations from drinking excessive amounts of caffeine, Aeshita Dwivedi, MD, a cardiologist at Northwell Health Lenox Hill Hospital, told Health.

Beyond just its effects on the cardiovascular system, caffeine has also been associated with insomnia symptoms. Overconsumption of caffeine may also increase the risk of anxiety or make it worse in those who already live with the condition. Though there’s both pros and cons associated with it, caffeine is considered healthy in moderation. The FDA limits safe daily consumption at 400 mg, but “everyone has a different tolerance, and it should be individualized based on your medical conditions,” said Dwivedi.

Are All Caffeine Drinks the Same?

Drinking too much caffeine isn’t recommended, regardless of whether you choose coffee, tea, soda, or an energy drink. However, caffeinated drinks are not all created equally. Beverages such as energy drinks can oftentimes not only exceed the recommended amount of caffeine for a day, but also contain added sugars and additional ingredients such as nitric oxide,” said Core.

Added sugars can contribute to poorer heart health and can also put a person at risk for weight gain and type 2 diabetes. And nitric oxide can increase oxygen content in the blood, which is not advised for people with preexisting heart conditions, Core added. But even if you are choosing healthier caffeinated beverages, it’s imperative that you’re not consuming too much caffeine.

If you’re experiencing insomnia, restlessness, rapid heartbeat, or an upset stomach, those might be signs that your caffeine consumption is excessive, Hopper said. “If you experience these symptoms, you should reduce your caffeine intake,” said Hopper. “The amount of caffeine that triggers these effects can vary depending on individual tolerance and how regularly you consume caffeine.”