Here’s a problem with energy drinks: Most who consume these caffeinated drinks don’t have just one. They sometimes drink two or three. They might also drink a couple of cups of coffee. Before they know it, the level of caffeine they’ve consumed is enough to set off cardiac complications, including atrial fibrillation or an arrhythmia. In some cases, just one hefty energy drink can put you at risk of heart complications.
Know your levels of caffeine
A report in the July/August 2016 Journal of Addiction Medicine suggests that energy drinks can be a danger to consumers. Prior studies have linked use of energy drinks to high blood pressure risk. Most are labeled with a warning for children and pregnant women to steer clear. Among teens and young adults, however, these drinks are all the rage. And the amount of caffeine per can or serving can range from less than one hundred milligrams of caffeine to a couple of hundred milligrams. Some have concentrated amounts of caffeine in a “shot,” so there’s a temptation to have a couple of shots, which can mean several hundred milligrams of caffeine.
In 2012, Consumer Reportstested 27 energy drinks and found that some had more caffeine than the label indicated, while others had less. Most had more than an eight-ounce cup of coffee (on average, 100 milligrams of caffeine). A few clocked in at 242 milligrams of caffeine per serving.
Safe levels of caffeine for a healthy adult hover around 400 milligrams a day, while pregnant women should limit caffeine to below 200 milligrams daily. Children should be limited to 45-85 milligrams daily, depending on the child’s size and weight. If you have any health conditions or take any regular medications, you need to consult with your doctor to determine safe daily levels of caffeine. Remember that the total milligrams per day should not necessarily be consumed in a brief period of time.
Some sample caffeine levels in popular energy drinks:
Monster Energy 16 ounces 160 mg
Mega Monster 16 ounces 240 mg
Java Monster 16 ounces 188 mg
Venom Energy 8 ounces 110 mg
Full Throttle 8 ounces 210 mg
5-hour Energy 1.9 ounces 242 mg
Rockstar Energy Shot 2.5 ounces 229 mg
Latest case of caffeine intoxication and atrial fibrillation
The report in the journal detailed the case of a 28-year-old male who presented to the emergency room after beginning to vomit blood. He was obese, with a heart rate of about 130 beats per minute (resting heart rate usually hovers between 60 to 80 beats/minute). An ECG diagnosed atrial fibrillation, a somewhat common arrhythmia that can lead to serious complications if it remains untreated. The doctor could only point to the fact that the patient shared he had been consuming two energy drinks daily for a while — 320 mg of caffeine plus a few beers (every day). The patient was also coincidentally diagnosed with a small esophageal tear, likely caused by forceful vomiting.
Previous cases of heavy consumption of energy drinks and cardiac events were also reviewed in the journal article. Caffeine and heavy doses of taurine, another common ingredient in energy drinks, were implicated as causative agents in the cases of the atrial fibrillation.
Don’t get tricked by ‘natural’ labels
Don’t be lured by the health halo that the word “natural” suggests. According to a study, energy drinks with natural on their label appear to lure consumers to buy them as a healthy caffeine source. Any and all kinds of energy drinks require careful label reading so you understand just how much caffeine you are consuming per serving. Natural is not a clearly defined term and does not offset caffeine levels.
Experiment: I drink a coffee and energy shot
I decided to experiment on myself and try an energy drink. I made the mistake of still having my regular large morning coffee 45 minutes before the energy boost. So within an hour, I was feeling the close to 400 milligram boost of caffeine. Let’s just say I felt quite jittery (pulse racing, hands a bit shaky) during my workout. I ended up abandoning the interval training program I had planned, for fear the caffeine would instigate an arrhythmia, and despite an hour of standard aerobic exercise, I remained revved up and jittery. I noticed I was really flushed after exercise and just felt buzzed.
My pulse remained elevated, closer to 90 for a couple of hours after exercise. My resting heart rate is usually in the high 50s. I also tend to have low blood pressure, about 90/60, and my blood pressure after exercise remained around 110/80 for a couple of hours. I’m also usually hungry within two hours of exercise, but I was not that day (the only plus). I passed on my standard lunch coffee and found that finally around 1 p.m., several hours after my java-plus energy shot, I was feeling back to normal.
My simple assessment: never again!
Amy Hendel, also known as The HealthGal, is a Physician Assistant, nutritionist and fitness expert. As a health media personality, she's been reporting and blogging on lifestyle issues and health news for over 20 years. Author of The 4 Habits of Healthy Families, her website offers daily health reports, links to her blogs, and a library of lifestyle video segments.