Bert and Ernie jump rope and munch apples and carrot. Cookie Monster has his namesake treat once a week, not every day. Can a Muppets mini-makeover improve kids' health, too?

A three-year experiment in South America suggests it can. Now, the "Sesame Street" project is coming to the United States.

Already, a test run in a New York City preschool has seen results: Four-year-old Jahmeice Strowder got her mom to make cauliflower for the first time. A classmate, Bryson Payne, bugged his dad for a banana every morning and more salads.

"What we created, I believe, is a culture" of healthy eating to fight a "toxic environment" of junk food and too little exercise, said Dr. Valentin Fuster, a cardiologist at New York's Mount Sinai Hospital.

Six years ago, he started working with Sesame Workshop, producers of television's "Sesame Street," on a project aimed at 3- to 5-year-olds.

"At that age they pay attention to everything" and habits can be changed, he said.

A clear need to do something

The need is clear: A third of U.S. children and teens are obese or overweight. Many don't get enough exercise, and a recent study found that kids' fitness has declined worldwide. They're at high risk for heart and other problems later in life.

"The focus is younger and younger" to try to prevent this, said Dr. Stephen Daniels, a University of Colorado pediatrician and a spokesman for the American Heart Association. The group's annual conference featured Fuster's experiment as one of the year's top achievements in heart disease prevention.

For "Sesame Street," the project offered a chance to improve viewers' lives and make over certain Muppets.

"While Cookie Monster is an engaging figure, we felt there was an opportunity there to really model healthy eating," said Jorge Baxter, regional director for Latin America for Sesame Workshop.

The new message is that certain things like cookies are "something you can eat sometimes, but there are some foods that you can eat all the time," like vegetables, he said. The healthy messages have been gradually incorporated into the television show, and its producers even made a doctor Muppet — Dr. Ruster (pronounced "Rooster") — in Fuster's image for the preschool project.

Showing results

The experiment in Colombia involved 1,216 children and 928 parents from 14 preschools. Kids had training on healthy habits and how the body works for an hour a day for five months using Sesame Workshop-produced videos, a board game, songs, posters and activities. Parents were involved through take-home assignments and workshops that focused on overcoming barriers to good food and exercise.

Children's weight and exercise habits were measured at the start and 1½ and 3 years later. Researchers documented a significant increase in knowledge, attitude and health habit scores among kids in the program vs. the comparison group.

The proportion of children at a healthy weight increased from 62 percent at the start to 75 percent at three years for those in the program.

In Colombia, that mostly meant that more undernourished kids grew to reach a healthy weight. In New York, where the program plans to launch in several early childhood and Head Start programs this spring and fall, project leaders will have to tackle under- and overweight kids.