A new study released by the Center for Digital Democracy and American University offers harsh criticism for online marketers when it comes to advertising top food brands to children online.

Kathryn Montgomery, a communications professor at American University who authored the report, told BusinessWeek that the rise in online marketing, especially websites run by food companies, has become a significant factor in the rising childhood obesity rates because they encourage kids to make poor food choices.

The food companies deny that charge. Kraft said it "reset its approach to youth advertising," several years ago. The company halted advertising to children under the age of 6 and says it only promotes "better-for-you" foods across all media to kids ages 6-11.

McDonalds and Kelloggs say they are working on industry self-regulation. But the Center for Digital Democracy has asked the Federal Trade Commission to step in.

The FTC is currently conducting a survey of food marketing to children across all media. As part of the study, the FTC has demanded that 44 food and beverage manufacturers, distributors and marketers disclose how they advertise to children.