DENVER, Colo. -- First lady Michelle Obama says she loves burgers and fries, but she wants her daughters -- and the rest of America's children -- to learn about better nutrition and exercise.

On Tuesday, she is launching Let's Move, a nationwide campaign to fight childhood obesity.

In an interview in Tuesday's USA Today, Mrs. Obama said the campaign will encourage more physical activity for children, healthier food in schools and more accurate food labeling. Some of her initiatives, such as tax breaks for grocery stores to move into poorly served communities, will require congressional action.

But before the program even launched, the first lady is under fire by leading organizations that work on eating disorder prevention and treatment after Mrs. Obama stated she put her children on a diet after her pediatrician and father felt they were getting "chubby."

"Being called chubby this day and age, for a female or a male is exquisitely damaging," said Dr. Anita Kumar-Gill, of the Eating Disorder Center of Denver.

"We can't focus on one single word," said Dr. Andrew Lieber, a pediatrician and medical director of Rose Medical Center's Teen Bariatric Center. "We have to tackle obesity and we have to get rid of this problem. It is the number one issue that is going to cost us money in the long run today."

Kumar-Gill said some kids will always be bigger than others because of their genetic make-up.

"To focus specifically on weight is a tremendous detriment, especially to the most vulnerable like adolescent boys and girls," said Kumar-Gill.

Dr. Lieber agreed and said the body mass index (BMI) is not a great indicator with kids because it does not take into account muscle mass.

"It is important that we talk about eating healthy, living a healthy lifestyle and not so much about diet," said Lieber.

"I would move heaven and earth to give my kids all the chance in the world for them to be at the top of their game in every way, shape and form," Mrs. Obama told the newspaper. "Let's Move operates under the principle that every family wants the same thing for their kid. So we're going to figure out how to make it easier for them to get it."

In an interview with ABC News, Mrs. Obama acknowledged: "I love burgers and fries. And I love ice cream and cake. And so do most kids."

But, she added: "We're not talking about a lifestyle that excludes all that. The question is how do we help people balance that out so that they're not facing life-threatening, preventable illnesses, but they're enjoying their food, they're eating their vegetables, they're doing their running and walking and playing and still have time to get a good, fun meal in every once in a while."