PHILADELPHIA The trend has emerged in big cities like New York and Los Angeles, as well as smaller places like Anchorage, Alaska, and Kearney, Neb. The state of Mississippi also has registered a drop, but only among white students.
Its been nothing but bad news for 30 years, so the fact that we have any good news is a big story, said Dr. Thomas Farley, the health commissioner in New York City, which reported a 5.5-percent decline in the number of obese schoolchildren from 2007 to 2011.
The drops are small, just 5 percent in Philadelphia and 3 percent in Los Angeles. But experts say they are significant because they offer the first indication that the obesity epidemic, one of the nations most intractable health problems, may actually be reversing course.
The first dips noted in a September report by the Robert Wood Johnson Foundation were so surprising that some researchers did not believe them.
Researchers say they are not sure what is behind the declines. They may be an early sign of a national shift that is visible only in cities that routinely measure the height and weight of schoolchildren. The decline in Los Angeles, for instance, was for fifth-, seventh- and ninth-graders the grades that are measured each year between 2005 and 2010.
Nationally, about 17 percent of children under 20 are obese, or about 12.5 million people, according to the Centers for Disease Control and Prevention, which defines childhood obesity as a body mass index at or above the 95th percentile for children of the same age and sex. That rate, which has tripled since 1980, has leveled off in recent years but has remained at historical highs, and public health experts warn that it could bring long-term health risks.
Philadelphia has undertaken a broad assault on childhood obesity for years. Sugary drinks like sweetened iced tea, fruit punch and sports drinks started to disappear from school vending machines in 2004. A year later, new snack guidelines set calorie and fat limits that reduced the size of snack foods like potato chips to single servings.
Change has been slow. But the message seems to be getting through.
Josh Monserrat, an eighth-grader at John Welsh Elementary, uses words like carbs, and portion size. He is part of a student group that promotes healthy eating. Still, he struggles with his own weight. He is 5-foot-3-inches but weighed nearly 200 pounds at his last doctors visit.
I was thinking, Wow, Im obese for my age, said Josh, who is 13. I set a goal for myself to lose 50 pounds.