William Dietz of the Centers for Disease Control and Prevention was quoted as saying he would like to believe "we are in the early stages of a social movement and there have been exceptional changes in what schools are doing in nutrition."
A conference on obesity is being held in New Orleans where about 1,800 researchers and general practitioners exchange views on ways to prevent obesity at the local level.
The campaign has shown favorable results, with a recent CDC study indicating a drop from 40 percent in 2000 to 18.8 percent in 2006 the number of school cafeterias offering only French fries as the only vegetable item in the menu.
Some 23 states receive funds from the CDC for their school anti-obesity programs.
For example, for the past three years Arkansas schools have recorded students' body mass. They have started to inform parents through letters if their child is overweight.
The ban on junk food in cafeterias and soft drinks in vending machines in Arkansas schools, combined with an emphasis on sports, has paid off in the state's war on obesity.
Earlier studies show that there are about 13 million obese children and adolescents in the U.S.
Those figures were attributed to television, fast food and soft drinks.
Meanwhile, there is an increase in the number of children being hospitalized due to health problems traced to obesity.
In a study presented to the conference, the number has tripled from 1998 to 2004.
These health problems include sleep apnea, high blood pressure and gall bladder stones.
John Morton, professor of medicine at Stanford University, said, that resulted in more admissions for obesity than for malnutrition in 2002 for the first time ever.
