This is part two on a series talking about caffeine. Aside from chocolate, caffeine/coffee is one of the most heavily researched foods. Scholarly journals in regards to caffeine or coffee come out on a weekly basis usually in support of the health benefits of what they have to offer. One of the things you might have heard about excessive caffeine consumption is that it can be bad for your heart – causing irregular heart beats. But has coffee gotten a bad rap over irregular heart beats? The truth might surprise you.

Does Coffee Cause Irregular Heart Beats?

High doses of caffeine have been linked to feelings of anxiety and palpitations (the feeling that your heart is beating out of your chest). In extreme cases, people can develop rapid hearat rates, metabolic acidosis, hyperglycemia, hypokalemia, respiratory alkalosis, and even die (4). We’ve all heard those stories of young teenagers consuming too many energy drinks and suffering the unfortunate fat of cardiac arrest (most likely attributed to caffeine intoxication and a preposition to an unknown cardiac issue).

Here’s what the research shows:

Acute ingestion of caffeine, especially for those who have a preposition to irregular heart beats, and for those people that don’t drink coffee on a regular basis, caffeine has shown that it can cause some irregular heart beats (4).

But what about people who drink coffee or take in other forms of caffeine on a regular basis? Does it warrant the risk? Let’s dive further.

How Coffee Causes Irregular Heart Beats

Excessive caffeine intake triggers a catecholamine response within the body. What the hell is a catecholamine response? Funny you should ask. Catecholamines are part of the fight or flight response. They’re also released during high times of stress from the adrenal glands which sit right on top of the kidneys. Excessive doses of caffeine can cause high levels of catecholamines to be released. Two major ones are epinepherine and norepinepherine. Both cause your heart to beat faster and contract harder. The two hormones also cause your blood vessels to constrict which can temporarily increase your blood pressure (2,3).

But don’t you have other hormones to reverse the response of fast heart rates? Yep. But as we showed in our article about caffeine and blood pressure, it blocks those hormones from working.

The good news is, in one of the first studies of its kind, the Journal of The American Heart Association took a look at long term caffeine users and its effects on the heart. The findings:

Out of almost one thousand four hundred people, long term caffeine use showed no evidence that “the frequency of habitual coffee, tea, or chocolate consumption was associated with cardiac ectopy [irregular heart beats] (1).

Just like caffeine and blood pressure, the body develops a tolerance from the response and unless the caffeine use is moderately high, it usually has no effect. Obviously, too much of anything is a bad thing.

However, you only know your body best. You might already be predisposed to irregular heart beats such as atrial fibrillation or might be more sensitive to the effects of caffeine than the person sitting next to you. In any case, stay thirsty my friends.


1. Dewland MD, T. et al. “Arrhythmia and Electrophysiology: Consumption of Caffeinated Products and Cardiac Ectopy.” Journal of the American Heart Association. 3 December 2015. Web. 25 March 2016.
2. Benowitz MD, T., et al. “Massive Catecholamine Release From Caffeine Poisoning.” The Journal of the American Medical Association. 3 September 1982. Web. 25 March 2016.
3. Klabunde PhD, R. “Circulating Catecholamines.” Cardiovascular Physiology Concepts. 5 May 2015. Web. 25 March 2016.
4. N.a. “Coffee.” Natural Standard – The Authority On Integrative Medicine. Web. 27 June 2016