Nicole Ostrow

Bloomberg News

The trend of rising obesity rates in the past decade may be reversing among U.S. preschoolers, according to the first national study to report a decline in the condition among young children.

The research by the U.S. Centers for Disease Control and Prevention found that the number of obese 2- to 4-year-olds from low-income families dropped 1.8 percent from 2003 to 2010, while those who were extremely obese fell 6.8 percent. The findings were published Tuesday in a research letter in the Journal of the American Medical Association.

Researchers attributed the decline to greater awareness of health problems caused by obesity as well as an increase in breast-feeding, which research has shown can reduce the risk. Obesity even at such a young age can set up children for diabetes, heart disease and even premature death, said Heidi Blanck, a study author.

Weve flipped from going up to really now showing a decrease, said Blanck, acting director of the Division of Nutrition, Physical Activity and Obesity at the Atlanta-based CDC, in a Dec. 21 telephone interview. Its a modest decrease but at least weve changed the direction. Were optimistic that with recent investments and recent initiatives well continue to see these numbers decline.

Researchers used data from the Pediatric Nutrition Surveillance System, which includes about 50 percent of children eligible for U.S.-funded maternal and child health and nutrition programs.

The study included 27.5 million 2- to 4-year-olds from 30 states and the District of Columbia.

The children were considered obese if their body mass index, a measure of height and weight, was at or above the 95th percentile for kids of the same age and gender.