Consumption of energy drinks may lead to increase in blood pressure, which can cause risk of serious cardiovascular events, a new study has claimed.
Anna Svatikova, of the Mayo Clinic in US and colleagues randomly assigned 25 healthy volunteers of age 18 years or older to consume a can (about 480 millilitre) of a commercially available energy drink and placebo drink within 5 minutes, in random order on 2 separate days, maximum 2 weeks apart.
The placebo drink, selected to match the nutritional constituents of the energy drink, was similar in taste, texture, and colour but lacked caffeine and other stimulants of the energy drink (240mg of caffeine, 2,000mg of taurine, and extracts of guarana seed, ginseng root, and milk thistle).
Energy drink consumption has been associated with serious cardiovascular events, possibly related to caffeine and other stimulants, researchers said.
The researchers examined the effect of energy drink consumption on hemodynamic changes, such as blood pressure and heart rate.
Participants were fasting and abstained from caffeine and alcohol 24 hours prior to each study day.
Serum levels of caffeine, plasma glucose, and norepinephrine (noradrenaline) were measured and blood pressure and heart rate were obtained at baseline and 30 minutes after drink ingestion.
Caffeine levels remained unchanged after the placebo drink, but increased significantly after energy drink consumption.
Consumption of the energy drink elicited a 6.2 per cent increase in systolic blood pressure; diastolic blood pressure increased by 6.8 per cent; average blood pressure increased after consumption of the energy drink by 6.4 per cent.
The average norepinephrine level increased from 150 picogrammes per millilitre to 250 picogrammes per millilitre after consumption of the energy drink and from 140 picogrammes per millilitre to 179 picogrammes per millilitre after placebo (74 per cent vs 31 per cent, respectively).
"These acute hemodynamic and adrenergic changes may predispose to increased cardiovascular risk," the researchers said.
"Further research in larger studies is needed to assess whether the observed acute changes are likely to increase cardiovascular risk," they said.
The study was published in the journal JAMA.