Consuming 32 ounces of an energy drink within a brief period might elevate blood pressure levels and heighten the risk of electrical disturbances in the heart, impacting its rhythm. According to a compact investigation detailed in the Journal of the American Heart Association, an open-access journal of the American Heart Association/American Stroke Association.
This particular study involved the participation of 34 individuals in good health, aged between 18 and 40 years. These participants were randomly chosen to consume 32 ounces of one out of two commercially available caffeinated energy drinks or a placebo beverage across three days. The consumption of these drinks was confined to a 60-minute timeframe, ensuring up to one 16-ounce bottle was consumed in half an hour.
The research team measured the volunteers’ heart electrical activity using electrocardiograms, which chart the heart’s beating pattern. Additionally, they monitored the blood pressure of the participants. These assessments were conducted at the commencement of the study and then every 30 minutes over four hours following the intake of the drinks.
The energy drinks under examination contained 304 to 320 milligrams of caffeine for every 32 fluid ounces. It’s generally believed that caffeine doses below 400 milligrams are unlikely to cause any electrocardiographic alterations. The energy drinks also comprised other typical ingredients such as taurine (an amino acid), glucuronolactone (a substance found in plants and connective tissues), and B vitamins. In contrast, the placebo beverage comprised carbonated water, lime juice, and cherry flavouring.
For individuals who ingested either type of energy drink, it was discovered that the QT interval—time required for the ventricles (heart’s lower chambers) to get ready for the next beat—was extended by six milliseconds or 7.7 milliseconds after four hours in comparison to those who had the placebo. An abnormal QT interval, being either too brief or too prolonged, may lead to irregular heartbeats, potentially resulting in life-threatening arrhythmias.
The findings of this investigation corroborate previous studies, indicating that the alterations in the QT interval are likely to persist throughout the four-hour observation period rather than being a transient effect post-consumption of 32 ounces of an energy drink.
Moreover, a statistically significant change in systolic and diastolic blood pressure was noted by 4 to 5 mm Hg in participants with energy drinks.
Sachin A. Shah, Pharm.D., the study’s lead researcher and a professor of pharmacy practice at the University of the Pacific, Thomas J. Long School of Pharmacy and Health Sciences in Stockton, California, stated, “We observed a correlation between energy drink consumption and alterations in QT intervals and blood pressure that cannot solely be ascribed to caffeine. It is crucial to delve into the specific ingredient or blend of ingredients present in various energy drinks that might elucidate the outcomes observed in our clinical trial.”
This study represents the most comprehensive controlled analysis of the impact of energy drinks on heart function and blood pressure amongst young, healthy volunteers to date. It’s estimated that around 30% of teenagers aged 12 to 17 years in the United States regularly consume energy drinks, which have been associated with an uptick in emergency room visits and fatalities.
“Given the widespread accessibility and frequent consumption of energy drinks by teenagers and young adults, including college students, comprehending the effects of these beverages on the heart is of paramount importance,” remarked Kate O’Dell, Pharm.D., study co-author, professor of pharmacy, and director of experiential programs at the Thomas J. Long School of Pharmacy and Health Sciences.
However, the study’s scope was limited to assessing the immediate effects of energy drink consumption and does not extend to long-term impacts or habitual intake of these beverages. Furthermore, the study exclusively evaluated the consumption of energy drinks in isolation, without considering the common practice of mixing them with other substances, such as alcohol. The research included only healthy individuals aged 18 to 40, and findings may vary across different demographic groups.
Dr. Shah emphasized the importance of public awareness regarding the potential effects of energy drinks on the body, especially for individuals with pre-existing health conditions. He also highlighted the need for healthcare professionals to advise certain patient groups, such as those with congenital or acquired long QT syndrome or high blood pressure, to limit or closely monitor their energy drink consumption.
More information: Sachin A. Shah et al, Impact of High Volume Energy Drink Consumption on Electrocardiographic and Blood Pressure Parameters: A Randomized Trial, Journal of the American Heart Association. DOI: 10.1161/JAHA.118.011318
Journal information: Journal of the American Heart Association
