A new study led by the Yale School of Public Health links energy drinks with hyperactivity in middle school children.

The study, released Monday, examined the effects that energy drinks such as Red Bull and Monster have on children ages 10 to 14. It found that those who consumed energy drinks were 66 percent more likely to score in the “at risk” category for hyperactivity and inattention symptoms. The study is cross-sectional — a data analysis of a population at only one specific point in time — so it is impossible to draw causal conclusions from it.

Nonetheless, medical experts interviewed warned against children consuming energy drinks.

“We don’t think there’s any reason anyone under the age of 18 should be drinking energy drinks — ever,” said Marlene Schwartz, co-author of the study and director of the Rudd Center for Food Policy & Obesity, a non-profit research center based at the University of Connecticut that focuses on food policy impacting obesity.

According to the report — which surveyed 1,649 New Haven middle school students from 12 different schools — with each additional energy drink consumed, middle school children are 14 percent more likely to display symptoms of hyperactivity and inattentiveness. The study showed that, on average, boys consume more energy drinks than girls, and Hispanic and African-American students were more likely to consume energy drinks than their Caucasian peers when adjusted for factors such as family structure and free school meal eligibility.

Professor of pediatrics and of psychiatry at the Yale School of Medicine James Leckman warned that these results are worrisome, noting that Yohimbine, a chemical in some energy drinks, is known to interact with some of the circuits in the brain that are involved in dopamine release. High doses of Yohimbine are known to cause psychotic episodes.

Jeannette Ickovics, the study’s lead author and director of the Community Alliance for Research and Engagement at the School of Public Health, said the middle school children surveyed drink an average of two or more sugar-sweetened beverages daily, with 10 percent of girls and 20 percent of boys drinking one or more energy drinks every day. She added that high consumption of energy drinks could negatively impact children’s school performance.

Schwarz and Ickovics said energy drink advertising should be regulated in order to limit consumption. Advertising techniques, including the way energy drinks cans are designed, are made to appeal to young males, Leckman explained. According to Schwartz, the same is true of the drink companies’ websites.

“[Their websites] basically feature cars and women in bikinis — it’s very clear who they are trying to appeal to,” she said.

While Ickovics acknowledged that it is unclear why African Americans and Hispanics are more likely to consume energy drinks, Schwartz suggested that targeted television advertising might be at play. TV programs that draw more African-American or Hispanic viewers tend to advertise energy drinks more, Schwartz said.

Leckman noted that peer pressure may be an additional element that causes children to consume energy drinks, but said that children must also enjoy the taste and effects of energy drinks, since it is unlikely that they would continue drinking them if it made them feel bad.

In the past, it has been difficult to protect children from harmful energy drinks because of the opaque nature of their caffeine content, but recently, transparency has improved, Schwartz said. In 2011, the Rudd Center published a study about the marketing of sugary drinks to children. It was impossible for the researchers to get data on the caffeine content of drinks from certain companies, she added.

“There were people whose jobs were literally to call companies and get this information, and even they can’t get it,” she said, adding that researchers checked the labels on cans, went to company websites and even tried calling the companies directly. Schwartz said she suspects that this information was being withheld because the companies are not legally required to disclose these details. But, Schwartz added, in an attempt to protect their reputations, they are now more forthcoming.

While all medical experts interviewed said that energy drink consumption among children is problematic, professor of pediatrics and Director of the Developmental-Behavioral Pediatrics Program Carol Weitzman said that it can also be dangerous for college students to drink them.

In fact, energy drink companies target most of their marketing toward college students, Schwartz said, explaining that this opens the door for medical problems such as caffeine addiction and caffeine intoxication, the latter of which causes heart palpitations that require emergency medical treatment.

“When you can’t stop [drinking energy drinks] even though you intellectually know it’s a bad idea — that’s a sign of addiction,” Schwartz said.

Beckman said that he had treated Yale College students who had abused stimulants to meet academic deadlines as inpatients in psychiatry after they experienced psychotic episodes resulting from stimulant abuse.

5-Hour Energy contains 208 milligrams of caffeine in each 1.9 ounce serving.

AMAKA UCHEGBU