Revealed: Exact number of coffees per day linked to deadly heart disease
Regularly drinking more than four cups of coffee per day may raise your risk of deadly heart disease, a study suggests.
Researchers found more than 400 milligrams of caffeine per day was linked to people's heart rate and blood pressure slowly increasing over time.
The team thinks the effect of caffeine on increased heart rate and blood pressure causes wear and tear on blood vessels and the heart, weakening and damaging them.
This can eventually lead an individual to develop heart attack, stroke or heart failure, they concluded.
There are roughly 90 mg of caffeine in one eight ounce drip coffee. The researchers said that drinking more than 400 mg per day increases your likelihood of developing cardiovascular problems
'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,' study author Dr Nency Kagathara said.
Dr Kagathara and a team of researchers from Zydus Medical College and Hospital in India arrived at these conclusions by studying 92 people with a healthy heart.
They tested the heart rate and blood pressure of each individual before and after they performed a three minute cardio exercise.
They also recorded information about their demographics and caffeine use - including whether they were partial to coffee, tea or soft drinks.
Almost 20 percent of the participants consumed more than 400 mg of caffeine every day.
That's equivalent to two Celsius energy drinks, roughly nine cups of black tea or 11 Coca Colas. For comparison, a venti Starbucks cold brew has 310mg.
The CDC and NHS recommend people don't drink more than 400mg per day - for pregnant women and those breastfeeding, the guidelines are lower.
The people who consumed more than 400mg per day were significantly more likely to have raised blood pressure and heart rate in general and after completing the three minute cardio session.
The researchers caution that their results could also be due to other differences between the participants - like their activity levels, age or other dietary habits.
But still, Dr Kagathara said, 'increasing awareness of these risks is vital to improve heart health for all.'
The people who were most likely to use caffeine in excess in this way were women who lived in urban areas and worked in a business environment.
These findings were presented at the American College of Cardiology Asia's 2024 conference, and have yet to be published in a scientific journal.
Drinking more than 400 mg of caffeine per day may cause a chronic rise in blood pressure, the researchers explained, which can increase your likelihood of developing cardiovascular problems like stroke
In short bursts, high blood pressure is harmless.
But constant high pressure puts strains on the body's blood vessels and heart muscles. This can lead to heart attack, stroke, heart failure , kidney problems, vascular dementia and eye problems.
A chronically high heart rate can cause similar complications.
Caffeine is the most widely used drug in the world. It works by temporarily blocking receptors in your brain that regulate sleep, memory, attention and learning.
This increases the flow of oxygen to the brain, speeds up your heart rate and improves concentration, which together can help you feel more awake.
It also can cause your blood pressure to increase. In high amounts, you might feel some unpleasant side effects - like headache, nausea, anxiety, jitters, an increased body temperature and flushed face.
In fact, if you drink more than 5,000 mg of it, caffeine can be fatal, according to the Centre for Addiction and Mental Health.
But older studies support the idea that drinking caffeinated beverages in moderation isn't harmful.
In fact, drinking a small amount of tea per day has been shown to help gut health and reduce risk of heart disease.
Some studies have even suggested that consuming a moderate amount of daily coffee might help people who work in offices live longer.
