Rod Stewart drinks them. Hilary Duff drinks the no sugar version. Snowboarder Shaun White keeps it in his coat pocket.

They're so-called "energy drinks," and while the quantity of caffeine is a cause of concern for many, the fact that some now come with alcohol has the attention of the Utah County Heath Department.

"An environment has been created where the consumer knows very little about the product," said Pat Bird, prevention manager for Utah County Substance Abuse.

"Most people aren't even aware that some energy drink manufacturers are adding alcohol to their beverages," Bird said. "They can be extremely hard to identify, using such phrases as 'malt beverage' and 'A-L-C by weight' to indicate they contain alcohol."

The cans look strikingly similar to the ones that don't have alcohol, so parents, and even store owners selling the beverages, are having a hard time telling the difference.

In fact, Bird said that's how the health department first became aware of the problem.

The department regularly conducts undercover "stings" where underage buyers attempt to buy alcohol. Eight months ago an underage buyer came out with alcohol -- but it wasn't beer, it was a familiar skinny can containing lots of caffeine. It was Tilt, whose parent company also makes Budweiser.

Bird said several purchases around the county have been successful, declining to say which retailers allowed the sales.

With no alcohol placement laws in Utah, Bird said alcoholic Rockstar drinks -- Rockstar 21 -- can be placed next to non-alcohol Rockstar, making it easy for them to be confused. While Bird said that usually isn't the case in most stores, the cans look similar and stocking mistakes can be made.

The fact that underage buyers may have access to the beverages isn't the only concern. Caffeine and alcohol have been a common mix in bars for years, but a depressant and a stimulant are not the best mix, as they send the brain conflicting messages.

The amount of caffeine in the beverages also concerns the health department.

A John Hopkins University study in 2003 shows that the average daily intake of caffeine a day is 280 milligrams. Simply drinking 100 mg a day can lead to physical dependence and feelings of withdrawal.

A 12 oz. can of Coca-Cola has 31 mg of caffeine, while a Pepsi has 35 mg. Compare that to an 8 oz. can of Red Bull, which has 88 mg of caffeine or a 16 oz. Rockstar, which doubles that at 160 mg of caffeine.

A 16 oz. Wired (344) will max out the daily dose and then some, with 344 oz. of caffeine.

The problem is, a 16 oz. can isn't very large and teens and 20-somethings usually drink more than one can.

"Anything in moderation is one thing, but they do four of five of them," said Lance Madigan, spokesman for the Utah County Health Department. "That's going to really cause some questionable health risks."

The John Hopkins study states that caffeine may have a role in delayed conception, lower birth rate, modest increases in blood pressure and a rise in cholesterol levels. It can also contribute to cardiovascular disease.

The boost that energy drinks give teens can clearly have a downside.

A 16-year-old in Lehi was prosecuted for impaired driving in November 2006. He passed the breathalyzer, but failed sobriety tests.

The culprit was several energy drinks that he'd sipped that day. Bird said it was multiple cans.

The drinks are marketed to teens and 20-somethings, with their fun names and slogans like "party like a Rockstar, and "cocaine: The legal alternative."

A new drink seems to be on the market every week, and Bird said that they are marketed to those feeling impulsive and rebellious.

Some are named after illegal drugs, or drug activity, such as Rehab, Shoot-ups, Cocaine or Ecstasy. The drink Chronic comes with a parental advisory, saying it is an "explicit drink."

"They use that favorable attitude around the drug culture to sell these products," Bird said.

It's a triple threat of access to alcohol, dangerous levels of caffeine, and normalizing the drug culture that the Health Department is trying to stop.

They want politicians to mandate better labeling for the drinks, so they more visibly indicate that they are an alcoholic beverage instead of a "malt" or A-L-C percentage. They'd also like to see product placement laws, so stores are penalized if the alcoholic drinks end up close to the non-alcoholic drinks.

Natalie Andrews can be reached at 344-2548 or nandrews@heraldextra.com.

This story appeared in The Daily Herald on page A1.