(NBC) -Think you're packing your kids healthy food when you pack their lunches for school? A new study says kids might be getting more in their lunch than you bargained for.
According to a new study conducted by the Cleveland Clinic, food that sits at room temperature all morning can get warm enough to breed bacteria - even when packed with ice packs.
"Parents are thinking that based on packing the lunches with ice pack is helping, but actually it's melting in a couple of hours," said Dr. Laura Jeffers with the Cleveland Clinic.
Jeffers says the bacteria growth could be enough to make kids sick.
"They're going to be ingesting food that bacteria has been growing on, so they could become ill, they could, you know, have vomiting or diarrhea," Jeffers said.
Researchers measured the temperatures of more than 700 preschoolers' sack lunches about an hour and a half before lunch was served.
More than 90 percent of the lunches with perishable food were found to be at an unsafe temperature. Bacteria can grow when perishable food reaches temperatures above 40 degrees.
By lunchtime, the average temperature for such foods had climbed to more than 60 degrees.
"Along with putting ice in there, if you freeze the drinks, it'll help keep things cold," Jeffers said.
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