Is Yerba Mate Dangerous?

Herbal teas have always been a source of joy and comfort for me. Among them, yerba mate was my favorite-- until one morning, when things went horribly awry. I was midway through my second cup when I was suddenly struck by an urge to vomit. I stood up but immediately fell over, dizzy, my heart pounding out of my chest. I ended up recovering without any trouble, but it didn't take me long to figure out what had gone wrong. I have tachycardia, or rapid heart rate-- and, while I'm generally careful to temper my caffeine intake, I had consumed an infusion of yerba mate that contained much more caffeine than I expected. My body reacted much in the way as it would to a few shots of espresso, producing an effect that would be benign for most people, but serious and uncomfortable for me.

This is one of the many potential dangers associated with yerba mate, a popular herbal tea originating in South America. Yerba mate contains caffeine, along with other strong natural stimulants. Healthy people, with no conditions affecting the heart or central nervous system, can generally drink moderate amounts of yerba mate without experiencing significant side effects. However, people who (like me) are especially sensitive to stimulants need to approach the infusion with as much caution as they would give toward any other caffeinated beverage, or suffer the possibility of an unpleasant reaction.

People who can not have caffeine or other stimulants are among the only people for whom yerba mate is absolutely contraindicated. If your doctor has advised you to avoid coffee and tea, shy away from yerba mate, as well. If you can safely drink caffeine, though, the occasional use of yerba mate is probably fair game and not dangerous.

However, like many herbal teas, yerba mate does contain some sketchy compounds that, over time, could increase your risk of certain diseases. Mayo Clinic nutritionist Katherine Zeratsky notes that, while yerba mate is safe for most people, it has been linked to cancers of the mouth, esophagus and lungs when consumed frequently, over long periods of time. This risk is especially serious for yerba mate drinkers who smoke. While an occasional cup of yerba mate tea is not dangerous, it's prudent to err on the side of caution and avoid drinking the tea on a frequent ongoing basis.

If you have any questions about your caffeine tolerance, your cancer risk, or the general safety of yerba mate, talk to your health care provider for advice and information. A qualified expert can help you make the choices that will benefit you.