Researchers say more than 70 percent of edible items endorsed by pop stars are either sugary drinks or nutrient-poor foods.

A 2012 commercial features a tense confrontation between the boy band One Direction and New Orleans Saints quarterback, Drew Brees.

Brees and the band’s front man, Harry Styles, argue backstage over the last can of Pepsi until band member Niall Horan chimes in.

“If you give him a Pepsi, you can be in the band,” Horan says.

“Really?” says Brees. Moments later, Styles is chugging the soft drink and Brees is on stage singing and dancing with the boys.

It’s one of many commercials featuring celebrities endorsing a food or drink that nutritionists consider unhealthy.

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In fact, 70 to 80 percent of the edible items touted by pop stars are either sugary drinks or high-energy, nutrient-poor foods, according to a study released today in the journal Pediatrics.

“We’re talking about really high fat or high sugar or high calorie items with very little fiber and proteins,” said Marie Bragg, Ph.D., the study’s lead author and an assistant professor at New York University’s School of Medicine.

That’s dangerous, she says, because these ads are likely to appeal to teenagers who idolize and seek to emulate celebrities in the music industry.

Meanwhile, the United States’ obesity problem — spurred in part by bad eating habits — extends to teenagers as well as adults. As of 2012, about 17 percent of children and adolescents in the Unites States were considered obese, according to the Centers for Disease Control and Prevention (CDC).

The Pepsi ad has been viewed almost 2.5 million times on YouTube. Commenter Navika S. wrote, “So u just have to give hazza a can of Pepsi to be in the band … MUM CAN I HAVE A CAN OF PEPSI FOR MY BIRTHDAY PLS.” (“Hazza” is a nickname for Styles.)

The study’s authors compiled a list of all the endorsements associated with stars featured on the 2013 and 2014 Billboard Hot 100 list and assessed the nutritional quality of each food or drink item they promoted.

They did not have a way to tease apart how many of the ads’ viewers were teenagers and don’t claim that the ads were designed to appeal to teenagers specifically. But they point out that the majority of the celebrities featured had been nominated or awarded a Teen Choice Award, suggesting they are indeed popular among that age group.

Angela Lemond, R.D.N., a practicing dietician and spokesperson for the Academy of Nutrition and Dietetics, agrees that pop stars can have a big influence on kids, but she thinks the obesity epidemic can be traced to a source closer to home.

“I personally have seen hundreds and hundreds of adolescents and I’ve never had someone say that they are actually drinking this product because a celebrity is,” she told Healthline. “I really think in all of my experience a majority of influence is parental influence.”

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Still, the food and beverage industry spends a lot of money trying to assert its own influence on children and teens — about $2 billion a year, according to the Federal Trade Commission (FTC).

The FTC also found that kids see over a dozen commercials per day for unhealthy food and drinks, despite a drop in TV ads overall. That’s not counting online and social media ad campaigns, which are becoming more popular and more creative.

For example, Doritos produced a series of online games that pull viewers and their friends into an interactive horror movie. To get to the end, the viewer needs a special code — accessible only on bags of their chips.

Advertising dollars spent on so-called “new media marketing expenditures” went up 50 percent between 2006 and 2009, according to the FTC report.

In 2006, the food and beverage industry responded to concerns over advertising junk food to kids by forming the Children’s Food and Beverage Advertising Initiative. So far 18 companies, including Pepsi, have pledged to limit their marketing to young kids or to ensure the products they do market to that age group meet a set of nutritional standards.

But that agreement only applies to kids under the age of 12, meaning advertising to teenagers is still fair game.

Elaine Kolish, the director of the initiative, which is a part of the Better Business Bureau, says older kids don’t need to be sheltered from advertising.

“As a society we’ve already decided that we’re going to afford our teens more rights, responsibilities, and privileges,” Kolish told Healthline.

Teenagers can drive, work, and in some states even get married, she noted.

“We don’t want to be a national nanny and tell people what they can and can’t see when they are over age 12,” she said.

She also cited a lengthy Institute of Medicine report that found “insufficient evidence” that TV ads influence the purchasing requests of kids over the age of 12.

Bragg, the pop star study’s lead author, agrees that it’s hard to tease apart the many factors that contribute to a teen’s diet. But, she says, being thoughtful about what and how we advertise to teenagers would help give parents “a fighting chance.”

“Maybe a middle ground is to advertise healthier products to teens,” she said, citing NBA star Steph Curry’s recent “Drink Amazing” campaign for Brita water filters.

Lemond, the nutritionist, echoed that sentiment.

“I’m a big fan of talking about what to emphasize instead of what to eliminate,” she said.

Parents should be thinking about their teenagers’ energy output as well as energy input, she added, by controlling their screen time and encouraging them to exercise.

Less time in front of the TV, computer, and smart phone should get kids moving and limit their exposure to ads for what Lemond calls “sometimes foods.”

“It’s all a balance,” she said.

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