Research on coffee and blood pressure is conflicting. However, it appears that how often a person drinks coffee may influence its effect on blood pressure.
In this article, we explain how coffee affects blood pressure and what the evidence says. We also discuss when to see a doctor and suggest alternatives to coffee.
How does coffee raise blood pressure?
Moderate coffee consumption may have a neutral or beneficial effect on hypertension in some people. Caffeine is a vasoconstrictor, which means it decreases the size of blood vessels and can increase blood pressure. Caffeine exerts its effects by interacting with various receptors in the brain. Experts believe that other compounds in coffee, such as antioxidants, have a protective effect on blood vessels. The benefits and risks of drinking coffee remain somewhat controversial, as research to date is inconclusive.
Long-term effects of coffee consumption
Increased coffee consumption is associated with a small decrease in hypertension, according to a 2017 review. Researchers found a 9% risk reduction by drinking 7 cups a day, with a 1% risk reduction for each extra cup per day. The same review suggested that beneficial compounds in coffee, such as phenols, may have a protective effect. The researchers also noted that genetic variations between individuals could affect how they metabolize caffeine.
Should people with high blood pressure avoid coffee?
A 2017 review concluded that people with high blood pressure should exercise some caution when consuming coffee, but need not avoid it. The review found that while older reports have pointed to a link between coffee drinking and hypertension, more recent studies have suggested that 3-4 cups a day has a neutral or beneficial effect.
A 2016 study in 40 healthy regular coffee drinkers found that all types of coffee raised blood pressure, but levels remained within healthy ranges.
The increase in blood pressure was temporary but still measurable 3 hours after consumption. Some research suggests that the amount of coffee a person drinks determines its effects on blood pressure.
A 2015 study indicated an increase in systolic blood pressure only in people who did not consume coffee frequently. Another review found that habitual coffee consumption of more than 3 cups per day did not increase the risk of hypertension. However, there was a slightly elevated risk associated with 1-3 cups per day.
Does decaffeinated coffee raise blood pressure?
Since coffee contains many different compounds besides caffeine, other compounds could be responsible for its effects on blood pressure. However, a person can try switching to decaffeinated coffee to see if their blood pressure goes down.
When to stop drinking coffee
Some people find that drinking coffee causes insomnia, anxiety, or tremors. Others may notice reflux and heartburn. Anyone who experiences these symptoms from coffee should avoid drinking it. Regular coffee drinkers may experience withdrawal symptoms, such as headaches and low mood, if they suddenly stop drinking. Therefore, if they wish to reduce their intake, they should gradually decrease the number of cups. The authors of a review in JACC: Clinical Electrophysiology note that some doctors recommend that people with atrial fibrillation or other disorders involving irregular heartbeat avoid coffee.
They concluded, however, that regular caffeine consumption of up to 300 milligrams per day appears to be safe and may even have a protective effect against heart rhythm disturbances.
The researchers cautioned, however, that if there is a clear association between arrhythmia episodes and caffeine, a person should not drink coffee.
Alternatives to coffee
Some coffee alternatives contain caffeine, while others are naturally caffeine-free. People can try:
dandelion root coffee
beverages made from barley or roasted cereals
When to consult a doctor
If a person experiences concerning symptoms when drinking coffee, they may wish to talk to a doctor. People who notice an increase in blood pressure should see a doctor.
Research suggests that people with high blood pressure can drink coffee as long as they are careful. Regular coffee drinkers may develop a tolerance to the physiological effects of coffee, while those who drink it less often may experience an increase in their blood pressure.
Coffee may be suitable for people with high blood pressure and may even have beneficial effects. However, people should be aware of their coffee tolerance and how their body reacts to caffeine. If a person is concerned about their blood pressure, they should talk to a doctor.