Healthy young adults who don't consume caffeine regularly experienced greater rise in resting blood pressure after consumption of a commercially available energy drink than those who had a placebo drink, according to a Mayo Clinic study.

The researchers alternately gave a can of a commercially available energy drink or a placebo drink to 25 healthy young adults, age 19 to 40, and assessed changes in heart rate and blood pressure.  Blood pressure and heart rate were recorded before and then 30 minutes after energy drink/placebo drink consumption, and were also compared between caffeine-naive participants (less than 160 mg of caffeine per day, a cup of coffee) and regular caffeine users (more than a cup of coffee equivalent of of caffeine per day). 

There was a marked rise in blood pressure after consuming the energy drink as compared to the placebo. The effect was most dramatic in people who did not typically consume much caffeine, researchers found. Overall, the blood pressure increase was more than doubled in caffeine naïve adults after consuming the energy drink vs. placebo, they found.

The concern is that the drinks could lead to increased risk for cardiac events.

"We know that energy drink consumption is widespread and rising among young people. Concerns about the health safety of energy drinks have been raised. We and others have previously shown that energy drinks increase blood pressure," says lead author Anna Svatikova, M.D., Ph.D., cardiovascular diseases fellow at the Mayo Clinic. "Now we are seeing that for those not used to caffeine, the concern may be even greater. Consumers should use caution when using energy drinks because they may increase the risk of cardiovascular problems, even among young people."

Upcoming at the American College of Cardiology's 64th Annual Scientific Session in San Diego.