CDC Reports Bafflingly Huge Obesity Decline Among 2-5 Year-Olds

This is pretty amazing:

New federal data published Tuesday show a 43 percent drop in obesity rates among children ages 2 to 5 during the past decade, providing another encouraging sign in the fight against one of the country’s leading public health problems, officials said.

….Researchers say that they don’t know the precise reasons behind the drop in obesity rates for children 2 to 5. But they noted that many child-care centers have started to improve nutrition and physical activity standards over the past few years. Ogden said that CDC data also show decreases in consumption of sugar-sweetened beverages among youth in recent years. Another possible factor might be improvement in breastfeeding rates in the United States, which helps fight obesity in breastfed children.

In fact, these results are so amazing that they’re hard to believe. This is a truly massive drop in a single decade for anything, let alone something as generally intractable as obesity. And it’s especially hard to believe because of this:

Overall, there was no significant change [in high weight] among infants and toddlers, obesity in 2- to 19-year-olds, or obesity in adults….There was a significant decrease in obesity among 2- to 5-year-old children.

That’s from the abstract of the study. I don’t have access to the full article in JAMA, but if I’m reading the abstract right, it means there was no change in obesity for infants age 0-2, no change for children age 6-19, and no change among adults. There was only a change in children age 2-5, and it was a huge one.

That’s just….inexplicable. In the past, about 8 percent of infants were overweight, and that increased to 14 percent among 2-5 year-olds. Now, there’s no obesity gain at all during those years. It’s 8 percent among infants and 8 percent among 2-5 year-olds. But obesity rates still increase to about 18 percent among older children. Whatever’s causing this drop in obesity rates is apparently affecting only 2-5 year-olds, but having no longer-term effect. It’s a stumper.