Energy drinks have been linked to heart, nerve and stomach problems. A recent study suggests consuming even one can might affect how well your blood vessels function, too.
Dr. Amit Khera, a cardiologist at Parkland Hospital and a professor of medicine at UT Southwestern Medical Center, says energy drinks deliver on the stimulation consumers want, but not in a healthy way. The drinks contain a lot of caffeine (the labels often don't say how much), other herbal and natural stimulants, and more sugar than sodas.
"It can affect your heart rate, your blood pressure, cause anxiety," said Khera, "and, as this study shows, may be unhealthy for your blood vessels, potentially to some heart problems down the road."
Doctors at McGovern Medical School at UT Health in Houston and colleagues studied 44 healthy, non-smoking medical students in their 20s by testing their blood vessel function before they drank a 24-ounce can of energy drink. Tested again 90 minutes later, the students' blood vessels dilated less after the energy drink than before.
“The lining of the arteries is sort of your defense mechanism, it’s the barrier. And once they cannot defend themselves, then cholesterol can get under you arteries,” says Khera. “Your blood vessels can change, so you get high blood pressure. You can develop atherosclerosis, so that measure of health can tell you who may have problems down the road.
Khera says the study’s one more reason for those seeking stimulation to opt for healthier alternatives like coffee or tea. Better still, he says, develop healthy sleep patterns. A good night's sleep can avoid the need for stimulants altogether.
About the study: “What they (researchers) are asking is this: If you just have one (energy) drink, what does that do to your arteries? Is it unhealthy for your arteries?”
What’s unhealthy about energy drinks: "First, energy drinks are thought to be stimulants – that’s why people take them - so they have a lot of caffeine. Coffee has about 100 milligrams. Energy drinks have anywhere from 100 to 300 milligrams. And if you look (at the label), it doesn’t actually tell you. They don’t have to label that, so you don’t know how much caffeine. They also have other stimulants – herbal and natural.
"And then finally, they have a lot of sugar in them as well. More sugar than sodas, commonly, so you may have in a 24 ounce or a 16 ounce as much as 15 teaspoons of sugar."
Why that’s harmful: "It can affect your heart rate, your blood pressure, cause anxiety and, as this study shows, may be unhealthy for your blood vessels, potentially to some heart problems down the road."
How energy drinks affect blood vessels: "To test the health of your arteries, you blow up a blood pressure cuff, then let go, and your arteries should dilate if their healthy. They gave these students one can of energy drink – 24 ounces they consumed – and then 90 minutes again, they did not dilate nearly as much, about half less."
Why that’s a problem: "The lining of the arteries is sort of your defense mechanism, it’s the barrier. And once they cannot defend themselves, then cholesterol can get under you arteries. Your blood vessels can change, so you get high blood pressure. You can develop atherosclerosis, so that measure of health can tell you who may have problems down the road."
Regular vs. chronic consumption of energy drinks: "Chronic consumption can raise blood pressure, can increase heart rate. There may be people who are vulnerable to that – people with high blood pressure or heart conditions. And let’s not forget the amount of sugar in there. So I think the main fear is that people are binge-drinking these – they’re drinking six, seven or eight – and then you’ll see a spike in ER visits. Those people are of concern as well."