Energy drinks may increase blood pressure, and lead to changes in the heart’s natural rhythm, according to a study presented at a meeting of the American Heart Association.
The drinks may make the heart more prone to electrical short circuits, HealthDay reports. The researchers noted it is not clear how much of the drinks’ effect is due to the caffeine in the drinks.
Researchers reviewed seven studies. They included 93 people who consumed energy drinks and had their QT interval measured. This interval indicates how the heart resets itself electronically while it beats. A longer interval increases the risk that the heart will develop a “short circuit,” a potentially deadly problem.
An additional 132 people consumed energy drinks and had their blood pressure measured. Most of the participants had one to three cans of Red Bull, the article notes.
The study found participants’ QT intervals were longer after they consumed energy drinks. Their systolic blood pressure (the top number in a blood pressure reading) increased 3.5 points after participants had the drinks, noted co-author Dr. Ian Riddock.
“QT prolongation is associated with life-threatening arrhythmias [heart rhythm problems]. The finding that energy drinks could prolong the QT, in light of the reports of sudden cardiac death, warrants further investigation.” Dr. Riddock said in a news release.
“The correlation between energy drinks and increased systolic blood pressure is convincing and concerning, and more studies are needed to assess the impact on the heart rhythm,” noted lead researcher Sachin A. Shah, Pharm.D. “Patients with high blood pressures or long QT syndrome should use caution and judgment before consuming an energy drink. Since energy drinks also contain caffeine, people who do not normally drink much caffeine might have an exaggerated increase in blood pressure.”