"Kids who are consuming energy drinks are more likely to smoke, they're more likely to try other illicit substances, they're more likely to drink alcohol. It's uncertain why there's this association but, certainly, the pattern is there," said Cecile Marczinski, an associate professor of psychological science at Northern Kentucky University.
Marczinski has studied the health effects of energy drinks, but was not involved in the new research. She added that several other recent studies have produced similar findings.
Other unhealthy behaviors that tended to accompany regular consumption of sports and energy drinks included more time watching TV and playing video games, the new study found.
The study, published online May 6 in the Journal of Nutrition, Education and Behavior, is one of the first to show that drinking these kinds of beverages may be part of an overall pattern of unhealthy behaviors, the researchers said.
Sports and energy drink consumption has tripled among teens in recent years, according to a 2013 study in the Journal of the Academy of Nutrition and Dietetics.
This new study surveyed nearly 2,800 middle and high school students from 20 public schools in the Minneapolis-St. Paul area during the 2009-10 school year.
Researchers asked the kids how often they had sports drinks like Gatorade and Powerade and energy drinks like Red Bull and Rockstar. They also asked about a wide variety of other health and lifestyle habits.
Nearly 40 percent of kids who took the survey drank an energy drink at least once a week. About 15 percent had at least one energy drink each week. Boys were more likely than girls to be regular consumers of either beverage type.
Kids who regularly drank sports drinks were more likely to play organized sports. They were also more likely to get more intense physical activity than those who didn't. But they also spent significantly more time playing video games each week. Boys who regularly consumed sports drinks spent more time watching TV than occasional users, the study found.
Both genders tended to drink more sugar-sweetened beverages overall, and they were more likely to have ever tried cigarettes if they regularly consumed sports drinks.
"Really, sports drinks are only needed for kids who participate in vigorous physical activity in hot, humid weather. Otherwise, if they're being consumed all the time they could be contributing to excess weight gain and tooth decay," said study author Nicole Larson, who is a senior research associate at the University of Minnesota, in Minneapolis.
She says that water is usually the best drink for active kids.
Regular consumers of energy drinks weren't more likely to exercise or play sports than kids who rarely drank the caffeinated beverages. But, they spent significantly more time playing video games. Boys who drank energy drinks averaged about four more hours of video game play weekly, while girls who drank energy drinks played about two more hours each week than occasional users.
Regular energy drink users consumed more sugar-sweetened beverages, and girls who regularly drank energy drinks were more likely to skip breakfast than girls who rarely or never drank them. Regular users of both sexes were more likely to have ever tried cigarettes, the study authors said.
"Energy drinks really don't offer any benefits for teens, and they create a risk for overstimulation of the nervous system. There have been studies linking energy drink consumption in kids this age to seizures, irregular heart rhythms and in rare, cases death," Larson said. "So if parents see some empty cans lying around, that might be a good time to encourage some more positive beverage options."
The American Beverage Association (ABA), which represents beverage manufacturers, said the study has a significant limitation.
"It's important to note that this research, which looks at association only, in no way shows that energy or sports drink consumption in any population causes 'negative' behaviors," said Maureen Beach, director of communications for the ABA.
But some feel the patterns noted in the study are concerning.
"If you think about even 10 years ago, kids didn't really consume high doses of caffeine like they do today. That has changed, and we don't really know the implications of that," Marczinski said.
High doses of caffeine in energy drinks may prompt the brain to look for other kinds of stimulants, either sugar or stronger kinds of stimulants, according to Marczinski.
"That's what the pattern of data is suggesting. You get sensitized on high doses of caffeine and suddenly other stimulants like nicotine from cigarettes are perhaps more appealing," she said.
Read what the American Academy of Pediatrics has to say about sports and energy drinks.