A decline in chubby babies and toddlers is providing a glimmer of good news in the fight against childhood obesity.
The trend was found in a study of children up to age 2 enrolled in a U.S. nutrition assistance program for low-income women and children. Half of all U.S. infants up to 12 months old are enrolled in the program.
The rate of youngsters at risk for obesity fell during the study, from almost 15 percent in 2010 to 12 percent overall in 2014, researchers from the federal Centers for Disease Control and Prevention reported Tuesday in the journal Pediatrics.
The rate declined in all ages studied. It was lowest—about 8 percent in 2014—for the youngest infants, from 3 to 5 months, versus almost 15 percent among toddlers.
The results were unexpected, given rising rates earlier in the decade, said CDC researcher David Freedman, the lead author.
"People are thrilled," he said.
Freedman said reasons are uncertain for the decline, but it came amid changes designed to improve nutrition and health in food packages, including more whole grains, fruits and vegetables. Also, breastfeeding among participating women increased in 2009 and that can protect against obesity.
The results echo a reported decline in older children in the program, referred to as WIC for women, infants and children. Also previous CDC data showed a similar decline in all U.S. youngsters from 2 to 5 years old, from about 14 percent in 2004 to 9 percent in 2014, coinciding with national campaigns targeting childhood obesity. Obesity rates tend to be higher in children from low-income families including WIC participants.
Dr. David Ludwig, director of obesity prevention at Boston Children's Hospital, called the results encouraging but said, "It's too soon to tell whether these new data represent a statistical fluke or evidence of real progress with the pediatric obesity epidemic. "
The researchers analyzed WIC survey data from 2000 to 2014 involving almost 17 million infants and young children. Rates increased early on, then remained stable from 2004 to 2010 until the decline.
Doctors don't usually describe babies as obese, but measure their risk using a weight-for-length ratio. Those with a high ratio, generally heavier than 95 percent of their peers, face an increased chance of becoming obese later on.
Whether the decline has continued is uncertain and the study didn't track infants to see if they became overweight or obese later on.
According to the CDC, U.S. obesity rates total almost 18 percent among all 6- to 11-year-olds and nearly 21 percent among 12- to 19-year-olds.
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