Energy drinks have a long-standing bad reputation because of their potential health risks, but this hasn’t stopped the public from frequently reaching for the cans loaded with caffeine, sugar, legal stimulants, and other additives.

While caffeine is often under scrutiny for its effect on the body, a new study showed other ingredients in energy drinks may be responsible. In the study, researchers found when the participants drank energy drinks, there were more changes in the heart’s electrical activity and blood pressure than when they drank another beverage with an identical amount of caffeine, but less of the other ingredients.

Read: Are Energy Drinks Dangerous For Heart Health? New Study Questions Risks, Nutritional Value

The researchers split up 18 young men and women into two groups. Half of the participants drank 32 ounces of an energy drink with 108 grams of sugar, 320 milligrams of caffeine, and other additives. The rest of the participants were given a carbonated drink with the same amount of caffeine, lime juice, and cherry syrup. After about a week when the beverages were flushed out of their systems, the participants switched drinks.

The subjects' heart activity were measured at the beginning of the study and at one, two, four, six, and 24 hours after drinking the beverage.

The electrocardiogram results revealed the energy drink group had a higher QT interval, which is a specific time measurement involving heartbeat, when compared to the caffeine group.

“If this time interval, which is measured in milliseconds, is either too short or too long, it can cause the heart to beat abnormally. The resulting arrhythmia can be life threatening,” said study author Emily Fletcher, in a news release.

Both groups also experienced an increase in systolic blood pressure, but after about six hours, the readings from the caffeine group slowed down and were almost similar to their original readings.

“On the other hand, those who consumed the energy drinks still had a mildly elevated blood pressure after six hours,” said Fletcher. “This suggests that ingredients other than caffeine may have some blood pressure altering effects, but this needs further evaluation.”

Furthermore, Fletcher notes larger clinical trials need to be conducted to further support these results.

In response to the study, the American Beverage Association released a statement: "Energy drinks have been safely consumed by people around the world for more than 25 years and nothing in this study of just 18 people refutes the safety of these products or their ingredients... It is also important to note that the raised blood pressure reported in this study was minimal – similar to what is experienced when climbing a flight of stairs – and, the researchers themselves say the results of the study are ‘not alarming.’”

See also: Dementia Research 2017: Caffeine Is Among 24 Compounds That May Prevent Dementia, Study Says

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