Does caffeine really affect heart health?

While the evidence is mixed on whether caffeine is bad or good, UCHealth cardiologist offers insights on how it affects your heart health.
Nov. 25, 2024
Is coffee good for you or bad for you? Studies contradict each other. Dr. Will Baker, a cardiologist with UCHealth Heart and Vascular Clinics in Steamboat Springs, says drinking coffee, like this woman in the picture, in moderation is not harmful. Photo: Getty Images.
Is coffee good for you or bad for you? Studies contradict each other. Dr. Will Baker, a cardiologist with UCHealth Heart and Vascular Clinics in Steamboat Springs, says everyone is different but for most people, drinking coffee in moderation is not harmful. Photo: Getty Images.

If you’re confounded by the constant and seemingly contradictory studies proclaiming that caffeine is either a benefit or a bust for your heart, you’re not alone.

But while medical professionals acknowledge that drawing conclusions can be difficult, they urge consumers to take the dueling research with a grain of salt (or sugar) and use common sense with their coffee intake.

“There’s a lot of confusion and uncertainty out there,” said Dr. Will Baker, a cardiologist with UCHealth Heart and Vascular Clinics in Steamboat Springs and Craig. “While the evidence is mixed, in general, there is no strong evidence that caffeine is bad for you. It’s probably fine, and possibly even beneficial if you limit it to about one or a few cups per day.”

The problem with studies that tout the advantages of eating or drinking certain foods is that they are observational in nature and draw conclusions from surveying the habits of large groups of people over a certain length of time, he said. A myriad of variables could alter the results.

A more valid approach would include two test groups – one that drank coffee and one that drank a placebo that tasted like coffee. After a certain length of time, researchers could study the link between various health-related issues and caffeine. These types of studies are limited regarding coffee.

“Lacking a study like that, it’s pretty hard to sort out a true cause and effect,” Baker said.

Not all coffee is created equal

Most of the studies that have been reported are limited to filtered coffee. Unfiltered coffee like espresso, French press or boiled ground-type coffee may be a different story.

Unfiltered coffee has higher levels of chemicals including cholesterol-raising diterpenes. These chemical compounds are diluted in filtered coffee since it goes through a paper filter, and they. can increase the level of LDL cholesterol, also known as “bad cholesterol.” LDL cholesterol levels are associated with a higher risk for heart attacks and strokes.

One solution does not fit all

In addition to different types of coffee, people will react to coffee and presumably caffeine differently, depending upon their body’s metabolism. Baker wants people to pay attention to their caffeine intake and its effects on their mood, sleep habits, body rhythms, alertness and overall feeling of wellness. It is also possible that other substances in coffee may be beneficial, such as antioxidants.

“There’s a lot of individual variability in how people will respond,” Baker said. “There’s also a degree of tolerance as people habituate to the effects of caffeine over time, so how much coffee you consume regularly can affect your response.”

Baker said patients arrive at his office after suffering a heart attack or experiencing heart irregularities like atrial fibrillation, which is a type of heart arrhythmia where the heart beats irregularly or too fast or too slow, and announce they are cutting caffeine cold turkey.

For some, it might make a difference. For others, it won’t.

“Some will go ahead and stop drinking coffee and their heart palpitations go away,” said Baker. “For others, cutting out caffeine doesn’t make a difference, so again, people respond in different ways.”

Be careful what you order

A bigger worry to him than a cup or two of joe for his patients are other selections available at a coffee shop or in a grocery store aisle.

Beverages such as caffeinated energy drinks, soft drinks and even some teas can contain up to five times as much caffeine as coffee. And then there are calorie-laded “coffee” options with a little caffeine and a host of dairy products and sugar that can pack as many calories as a milkshake.

“These energy drinks are often loaded with large amounts of caffeine or other stimulants, while some of the coffee drinks are laden with sugar and other substances with little or no nutritional value,” he said.

Baker said some of the best advice he dispenses comes back to what your mother and grandma may have extolled: Don’t do anything to excess.

“I’ve never told anyone to stop drinking coffee,” he said, “so go ahead and enjoy your caffeine. But like anything, just do it in moderation, and pay attention to how it affects you.”

About the author

Mary Gay Broderick is a Denver-based freelance writer with more than 25 years experience in journalism, marketing, public relations and communications. She enjoys telling compelling stories about healthcare, especially the dedicated UCHealth professionals and the people whose lives they transform. She enjoys skiing, hiking, biking and traveling, along with baking (mostly) successful desserts for her husband and three daughters.