1147 GMT March 31, 2020
Researchers found that drinking four cans of a commercially available energy drink caused abnormal changes in the heart’s electrical activity and blood pressure that were absent when volunteers drank a control drink that contained the same amount of caffeine, according to telegraph.co.uk.
Study author Emily Fletcher, of the David Grant USAF Medical Center at Travis Air Force Base in California, said, "We decided to study energy drinks’ potential heart health impact because previous research has shown 75 percent of the base’s military personnel have consumed an energy drink. And nearly 15 percent of military personnel, in general, drink three cans a day when deployed, which is more than we studied here."
For the study, 18 participants were divided into two groups. One group was given 32 ounces (just under a liter) of a commercially-available energy drink, which contained 108g of sugar and 320mg of caffeine.
The other group was given a control drink containing 320mg of caffeine, 40ml of lime juice and 140ml of cherry syrup in carbonated water.
Researchers monitored the participants' heart activity and blood pressure for six hours after consuming the drinks, with follow-up examinations the next day.
Both groups experienced similar increases in systolic blood pressure after drinking the drinks.
However, in the control-drink group systolic pressures had almost returned to their original readings after six hours.
Fletcher added, “On the other hand, those who consumed the energy drinks still had a mildly elevated blood pressure after six hours.
“This suggested that ingredients other than caffeine may have some blood pressure altering effects, but this needs further evaluation.”
Based on this preliminary evidence, Fletcher said that people who have high blood pressure, underlying cardiac conditions or other health issues might want to avoid or use caution when consuming energy drinks until more is known about their impact on heart health.
“This is a small study and further studies are needed to confirm these results.”
Gavin Partington, director general of the British Soft Drinks Association, said, “Caffeine in energy drinks is no different to caffeine in coffee so these findings are somewhat odd.
"The European Food Safety Authority latest opinion confirms the safety of energy drinks and their ingredients and therefore does not provide any scientific justification to treat energy drinks any differently to the main contributors to daily caffeine intake including tea, coffee and chocolate.
"It's also worth remembering that coffees from popular high street chains contain the same or more caffeine than most energy drinks."