Vigilant Parents Say They Are Often Unaware of Marketing Techniques That Draw Teens, Kids;

The food industry is spending millions of dollars on slick digital marketing campaigns promoting fatty and sugary products to teenagers and children on the Internet, on cell phones and even inside video games -- often without the knowledge of parents.

It used to be that food companies reached children mainly through television commercials broadcast during cartoon programs.

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But now companies maintain flashy Internet sites with eye-catching graphics that allow kids and teens to interact with brand mascots, create their own characters, and even make their own ads and send them to friends.

Watch "World News" this evening for a full report on the eye-catching marketing of foods to children.

The effort extends to social-networking sites such as Twitter and Facebook, where companies have created fan pages and posted applications promoting their drinks and candies. On YouTube, kids can watch viral videos from Burger King and other food giants.

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The marketing gurus behind Fanta soda have even developed technology that teens can download on their cell phones, which allows them to send audio messages to each other at high frequencies, sounds that adults over 25 cannot hear.

This digital marketing, critics say, flies under the radar of most parents -- even those who consider themselves vigilant about what their children watch and eat. Indeed, some parents told ABC News they have no idea such marketing even exists.

"I was very unaware of the fact that there were these commercials that were popping up on the Internet," said Alison Paul of Windham, N.H., a single mom whose son has struggled mightily with his weight.

"It does not make me happy to know that I'm working so hard to try and give my son a healthy life, and when the outside world is working against me, it's frustrating," she said.

Paul's son, Eli, 13, added, "I have seen them in video games and I've seen them on TV and on Facebook. It's annoying. You know, you don't want this big burger flashing in your face."

Jeffrey Chester and Kathryn Montgomery, themselves parents of a teenage girl, have been researching what's called "360 Marketing." Chester runs a watchdog group called the Center for Digital Democracy in Washington, D.C.; Montgomery is a professor of Communication at American University.

"The production values now on these sites are very professional -- full-motion video, often 3-D quality, terrific sound and high-quality animation. So this is not just an old-fashioned Web site; this is a really immersive experience that we're allowing kids to enter," Chester said.

"And in many ways it's really like becoming part of the commercial," his wife added.

Age-Screening Technology Is Not Always Foolproof

At, kids can create their own avatars, dance to the Reese's Puffs rap and then share their dance with friends.

Like Reese's Puffs, Trix cereal is owned by General Mills and operates a site at that goes far beyond its old television spot featuring a bouncing rabbit and the slogan, "Trix Are for Kids!" Children can enter a colorful "Trix World" where they can bowl at "Fruitalicious Lanes" or explore a "Rabbitropolis" that has a movie theater showing "Trix Toons."

Hotel 626 is a haunted house available only on the Web designed by the Doritos brand. Visitors are trapped inside the hotel. The program uses your webcam to sneak a picture of you. Until recently, one of the only ways to get out was to provide a crucial piece of personal information -- your phone number.

Doritos says it no longer collects phone numbers and insists that Hotel 626 is not aimed at children under 18. But it's not hard for, say, even a 9-year-old to fool around on the site. All the child has to do is lie about his or her age -- and he or she is in.

Chris Kuechenmeister, a spokesman for Frito-Lay, which owns Doritos, told ABC News the site's age-screening technology is also "commonly used by a range of other companies."

He added, "While we believe we have put effective control into place to properly screen visitors, we are always looking for ways to enhance the security of our consumers and Web sites."

Indeed, many food sites claim they are not for children. Coca-Cola says its "Happiness Factory" is aimed at kids over 12. But critics say their eye-catching, colorful games and graphics seem tailored to a younger audience.

Coca-Cola told ABC News it "does not market any of its products to children under 12."

ABC News tried to show some of these sites to Dan Jaffe, who lobbies for the advertising industry. He said he didn't want to talk specifics. He did say, however, that government and the industry itself had established a well-functioning system of regulation.

Asked whether the Doritos site that procured phone numbers went too far, Jaffe said, "I'm just not going to try and make that judgment. But I must say to you that we set up a system to deal with these types of issues."

He also downplayed any link between advertising and the epidemic of childhood obesity in America.

"We hear over and over again it's the advertisers -- 'Let's stop the advertising. If we only stopped the advertising the obesity rate would suddenly go down' -- I just think there's no data to suggest that," said Jaffe, executive vice president of the Association of National Advertisers.

Food Industry Says Responsibility Lies With Parents, Too

But a major study by the Institute of Medicine says that "food and beverage marketing to children represents ... at best, a missed opportunity and, at worst, a direct threat to the health of the next generation."

David Ludwig, an associate professor at the Harvard Medical School and director of the Optimal Weight for Life program at Children's Hospital Boston, said, "The food industry wouldn't be doing it if it didn't work."

"The food industry loves to promote itself as a responsible corporate citizen -- a stakeholder, if you will, in the obesity epidemic. And while there are some more responsible entities in the food industry, overall they've been in the forefront of reducing nutritional quality for children to its lowest common denominator," he said.

The food industry also argues it is up to parents to keep an eye on their children, the Internet sites they visit and the video games they play.

Single mom Allison Paul says that is not always possible.

"I mean, he's 13 years old. What am I supposed to say to him, 'OK, sit down here and let me look at what you're doing at all times on the computer.' I mean it's hard," she said.

"As a mom who's trying to teach their children a healthy lifestyle, knowing that this is happening -- it's scary," Paul said.

Mary Engle, head of the Advertising Practice Division of the Federal Trade Commission, said that given the companies' right to freedom of speech there is only so much regulating the government can do. She said the Internet and flashy Web sites are part of the "the world we live in and that's why parents need to be vigilant."

"It's absolutely a challenge but there' no regulation that's going to be able to substitute for parental monitoring and supervision of their children," she said.