Instead, based on surveys of more than 7,000 middle-schoolers, researchers found that some kids may drink less milk as they grow older, but their consumption of soda and other sweetened drinks remains fairly steady. Sugary drink intake did not appear to be rising to replace milk.

The findings were "kind of surprising," said Solveig Cunningham, one of the study's authors and an assistant professor at Emory University. "Kids have a tendency to drink more of everything or less of everything."

On the one hand, it's good news that kids aren't ditching milk for less healthy drinks.

But on the other hand, Sara Bleich, an assistant professor at Johns Hopkins Bloomberg School of Public Health, said, "It suggests to me that when people drink calories in liquid form, they don't compensate for that. It doesn't fill you up, and they are just adding those calories on top" of what they're already eating and drinking.

Earlier studies had pointed to a tendency for kids to replace milk and pure juices with sugar-sweetened drinks.

Cunningham and her colleagues looked to a large survey of nearly 7,500 school children who were followed between 2004 and 2007 to see whether that is the case.

In the fifth and eighth grades, the kids filled out questionnaires about what they typically drank and how much.

They found that kids did drink less milk as they got older.

For instance, about 53 percent of fifth graders drank milk daily compared to 46 percent of eighth graders.

At the same time, the percentage of kids who drank sweetened beverages on a daily basis in fifth and eighth grade held steady, at around 27 to 29 percent.

The researchers determined that the change in how much milk kids drank was unrelated to the change in how many sweetened drinks they consumed.

"This pattern indicates that sweetened beverages did not displace other caloric beverages from children's diets," Cunningham and her colleagues write in the Journal of the Academy of Nutrition and Dietetics.

Dr. Claire Wang, an assistant professor at Columbia University's Mailman School of Public Health, said the findings are interesting, "but I wouldn't say this is conclusive evidence."

The nature of the survey makes it a challenge to be sure that kids are reporting what they drink accurately, she pointed out.

They have to recall how many glasses of each type of drink they had in the past week.

"Even for an adult it's a pretty difficult task," Wang told Reuters Health.

The study had some strengths too, she added, given that it was large and nationally representative.

Whether the result truly reflects kids' drink choices or is a consequence of how drink consumption was measured "it provides us with some really interesting questions to answer," she said.

Cunningham said one of the elements missing in the study that she would like to explore is how much water the kids drank.

Among the kids who continued to drink a lot of milk and sugary beverages, it's possible that they are not drinking water, and instead are encouraged to drink milk, juice or soda.

Bleich said kids need to be taught that water is a good option.

"Kids are taking in a lot of calories in liquid form," said Bleich. "We should get kids to drink fewer calories from any sort of liquid, so we should get them to drink more water."

SOURCE: bit.ly/MVdERu Journal of the Academy of Nutrition and Dietetics, online July 23, 2012.

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