Is Caffeine Raising Your Blood Pressure?

Caffeine turns a drink into jolt juice. So, as you sip on your cup of coffee or slam down an energy drink, you often FEEL the effect as the caffeine flows into your system. It can strike like a thunderbolt.

But did you ever wonder what that liquid oomph does to blood pressure (BP)? Given that nearly half of all adults in the United States live with high blood pressure (hypertension), that’s an important question.

For an answer, we turn to cardiologist Luke Laffin, MD.

How caffeine impacts blood pressure

Caffeine is the world’s most-used natural stimulant. It has long been a go-to energy source for anyone needing a boost. (FUN FACT: Legend has it that a ninth-century goat herder discovered the magic of coffee beans after his grazing animals ate them and wouldn’t sleep.)

But caffeine does more than just deliver a buzz to your body.

The psychoactive substance also narrows (or constricts) your blood vessels, says Dr. Laffin. The tightening forces your heart to work harder, which increases the pressure needed to pump blood throughout your body.

The increase in blood pressure typically takes place within 30 minutes of drinking a caffeinated beverage and peaks after about an hour.

“Then, it will linger for a bit before your blood pressure comes back down,” says Dr. Laffin.

A blood pressure reading of 120/80 is typically considered the upper edge of what’s considered healthy. (Those measurements for systolic and diastolic blood pressure are units of pressure known as millimeters of mercury, or mmHg.)

A morning cup of coffee can potentially raise your blood pressure by up to 10 mmHg, which may be enough to push you into a range that’s classified as stage 1 hypertension. A second, third or fourth cup keeps those numbers climbing, too.

“Caffeine can move your blood pressure from what’s considered ‘controlled’ to ‘uncontrolled’ pretty easily,” he adds.

Should you limit caffeine intake?

Like many things in life, caffeine is best enjoyed in moderation.

Research shows that most healthy adults can consume up to 400 milligrams of caffeine a day with no adverse health effects. (To put that in perspective, an 8-ounce cup of regular coffee typically has 80 to 100 mg of caffeine.)

In general, concern over elevating your blood pressure isn’t a reason to swear off coffee if your BP is in a healthy range.

“A moderate amount of coffee is probably OK for you,” reiterates Dr. Laffin. “If you start measuring your coffee consumption by pots or you’re chugging energy drink after energy drink, it’s a different story. It can become a problem.”

If you’ve been diagnosed with high blood pressure, limiting your caffeine intake to below 400 mg is recommended. Talk to your healthcare provider about what your daily caffeine cap should be.

Can your BP build a caffeine tolerance?

Caffeine hits everyone differently. Some might get the jitters after a single cup of java. Others may be able to rotate fresh cups of brew on their desk all day without ever really feeling revved up.

But not feeling the effects of caffeine doesn’t mean it’s not impacting your body. Caffeine consumption DOES bump up your BP and heart rate — and over time, that strain on your cardiovascular system can take a toll.

“It’s best to observe some limits,” advises Dr. Laffin.

If you feel like you can’t function without large doses of caffeine, it’s probably best to ask yourself why.

“Take a hard look at why you might need so much caffeine,” he recommends. “Are you not getting enough sleep? Is there some sort of medical issue making you tired? Is it stress? These are questions worth asking.”

And getting an answer can’t hurt when it comes to better managing your blood pressure.