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Alarmed at the rates of obesity among young people, the children's program Sesame Street is embarking on a drive to educate its audience about the benefits of healthy eating. As part of the project, some of the show's favorite characters are getting nothing less than a makeover -- Cookie Monster is going on a diet, while Elmo has started professing a love for exercise.

The producers of Sesame Street, which kicked off its 36th season on public television in the U.S., said each episode will now start with a health tip about nutrition, exercise, hygiene and rest. Dr. Rosemarie Truglio, the show's vice president of research and education, said that the program long had focused on emotional and physical health but that, given the rise in obesity, the producers were pushing the message about the need to have healthy food and participate in exercise.

As part of the project, Cookie Monster, who used to sing that "C is for cookie," will be telling viewers that the items are occasional treats. He now sings, "A cookie is a sometimes food."

Producers deny that Cookie Monster has been placed on a diet. "We would never use the word diet with pre-schoolers," said a spokeswoman. However, behind the makeover are depressing statistics on child health. Almost one in three children in the U.S. is now overweight. Ironically for the makers of Sesame Street, one of the main reasons cited is that children spend too much time watching television.