How Long Can Caffeine Raise Your Blood Pressure?

Caffeine is a naturally occurring stimulant found in the leaves, seeds, and nuts of several plants, such as:

• Coffea arabica, used in coffee
• Camellia sinensis, used in tea
• Cola acuminata, included in soft drinks
• Theobroma cacao, a part of cocoa and chocolate
• Paullinia cupana, used in snack bars and energy drinks

Caffeine does not have a distinct flavor, nor does it have any nutritional value. Nevertheless, in the U.S., over 90% of adults consume caffeine daily. The average caffeine intake in U.S. adults is roughly 4 milligrams per kilogram daily, equivalent to around two to four cups of brewed coffee.

Once caffeine enters your system, it works on the central nervous system, which has far-reaching effects on several physiological and mental functions. Of particular concern are its effects on your blood pressure and heart health.

Many foods and drinks contain caffeine, and research suggests it’s currently the most widely consumed drug in the world. Unlike other psychoactive compounds, though, caffeine is legal. In fact, caffeine is even an active ingredient in many beverages and foods endorsed for children. Still, while it has health benefits, you should keep in mind that consuming anything in excess is not healthy.

Beverages like coffee, tea, and sodas are major caffeine sources. Caffeine in these beverages is quickly absorbed by your gastrointestinal tract and dissolves in the water and fat cells inside your system. Caffeine can then cross the blood-brain barrier and enter your brain, impacting several brain and cognitive functions – the most important effect being an increase in your awareness, energy levels, and feelings of well-being.

However, too much caffeine may lead to side effects, such as troubled sleep, irritability, and gastric issues. Research shows that people often become dependent on caffeine, a dependency that borders on substance use disorder.

The short answer to this question is “yes.” Some studies suggest that caffeine blocks the hormonal activity that widens arteries and causes a spike in adrenaline release, leading to elevated blood pressure. Studies also reveal a higher average blood pressure in regular coffee drinkers than in those who don’t drink coffee.

Caffeine can elevate your blood pressure for a short while, even if you don’t have a history of high blood pressure. Sometimes, the spike in your blood pressure can be sudden and striking. That depends on the specific individual, though.

According to the U.S. Food and Drug Administration, around 400 milligrams of caffeine intake every day is considered safe for most people. At the same time, the American College of Obstetricians and Gynecologists recommends pregnant women limit their caffeine intake to 200 milligrams daily, while the American Academy of Pediatrics advocates children below 12 avoid foods and beverages containing caffeine. If you have teenagers above 12, limit their caffeine intake to 100 milligrams per day.

If you’re concerned about the effects of caffeine on your blood pressure, ask your doctor about the ideal daily intake and when you should stop taking caffeine. Also, note that the caffeine content in beverages such as coffee and energy drinks may vary depending on the brand and the preparation.

If you have high blood pressure, it’s better to avoid caffeine before strenuous activities such as exercising or physical work.

Interestingly, while research suggests a temporary spike in blood pressure right after caffeine intake, it doesn’t seem to have long-term effects. A 2017 study revealed that caffeine intake in the long term actually reduces the risk of hypertension. The study, which involved more than 200,000 participants, found a 9% reduction in the risk of hypertension when individuals drank more than seven cups of coffee daily. The study also indicated a further 1% reduction in the risk of hypertension for every additional cup of coffee every day.

Other studies have similarly linked long-term caffeine intake with several health benefits. Caffeine-containing beverages like coffee are rich in antioxidants that reduce the harmful effects of free radicals, which cause oxidative stress.

A 2018 study found that regular caffeine intake also lowered the risk of cardiovascular diseases by 15% in healthy individuals with no medical history compared to those who don’t drink coffee. The study also revealed that caffeine intake does not increase the risk of a cardiovascular event in individuals with an existing cardiovascular condition. That being said, the study recommends that people with already high blood pressure exercise caution.

According to a 2008 study, caffeine causes a spike in blood pressure within 30 minutes. Peak blood pressure typically happens between one to two hours after caffeine intake, and this spike may last for over four hours. The study also revealed that the increase in blood pressure would be between 3 to 15 millimeters of mercury (systolic) and 4 to 13 millimeters of mercury (diastolic) following caffeine intake.

If you want to understand how much caffeine raises your blood pressure (or whether it even causes a spike), first check your blood pressure before you drink a caffeinated beverage. Wait 30 minutes to two hours before measuring your blood pressure again. If you notice a spike, that means you may be vulnerable to elevated blood pressure due to caffeine.

You can ask your doctor what this means for you and what you can do to prevent the harmful effects of caffeine. They will be in the best position to advise you on the best way to move forward. Keep in mind that suddenly cutting off caffeine intake may cause withdrawal headaches, so you may be better off weaning away from caffeine gradually. The symptoms may be intense for a few days but usually subside after a week.