Obesity rates fell among U.S. preschool-age children in 2010, reversing a trend of the past decade, according to the first national study to spot a decline in the condition among young kids.
The rate of obese 2- to 4-year-olds from low-income families dropped 1.8 percent in 2010 from 2003, while it fell 6.8 percent for those who were extremely obese, the U.S. Centers for Disease Control and Prevention reported in a research letter published 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 studies have 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.
"We've flipped from going up to really now showing a decrease," Blanck, acting director of the Division of Nutrition, Physical Activity and Obesity at the Atlanta-based CDC, said in a Dec. 21 telephone interview. "It's a modest decrease but at least we've changed the direction. We're optimistic that with recent investments and recent initiatives we'll continue to see these numbers decline."
Previous studies had shown that obesity levels may have reached a plateau in various age groups, she said.
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, while extreme obesity was defined as having a body mass index at or above 120 percent of the 95th percentile. That means, a 3-year-old boy of average height who weighs 37 pounds or more would be considered obese, while a 3-year-old boy of average height who weighs 44 pounds or more would be extremely obese.
The prevalence of obesity dropped to 14.94 percent in 2010 from 15.21 percent in 2003, according to the report. It was still higher than 13.05 percent in 1998. While the percentage of preschoolers with extreme obesity declined to 2.07 percent in 2010 from 2.22 percent in 2003, it was still higher than 1.75 percent in 1998.
Of the 2.4 million included in the study in 2010, there were 359,222 obese and 49,772 extremely obese U.S. preschoolers, Blanck said.
During the time the children in this study would have been breast-feeding, the number of low-income infants nursing jumped more than 10 percent, she said.
"The trends of obesity and extreme obesity among U.S. low- income, preschool-aged children changed around 2003," Blanck said. "I am optimistic that continued efforts to support nursing mothers and improved obesity prevention resources for parents and the nation's child care centers and early education setting will help keep this downward trend a reality."