Your child's lunch box may be carrying more than food, according to a recent report from the journal Pediatrics. Researchers in Texas found that very few of the foods in school lunch bags or boxes were chilly enough to prevent the growth of bacteria that can cause food-borne illnesses. What are the risks? Here's what you should know:

How was this study conducted?
A team of researchers examined the home-packed lunches of more than 700 preschoolers, and discovered that almost 40 percent of them didn't contain an ice pack. And even those lunches that contained two or more ice packs weren't always safe — only 8 percent of the items in those lunch boxes stayed properly cool. Overall, a surprising 90 percent of the lunches were at unsafe temperatures. "This study should be an eye-opener for the public," says researcher Fawaz Almansour, as quoted by TIME.

Did the researchers find any actual cases of bacteria-plagued lunches?
No, which some critics say is a real weakness of this study. "This is a provocative study," says Dr. Michael Green, as quoted by MSNBC. "But there is a missing piece: It doesn’t tell you what this does to the relative risk of disease." There may be only a small added risk from eating a lunch that's been stored at room temperature, and many parents have expressed skepticism that this study shows evidence of a real problem. 

What's the right way to pack a lunch?
Experts recommend freezing foods and drinks when possible, and packing them when they're still frozen — that way, foods stay colder. Insulated lunch packs are a good idea, as is using a refrigerator to store lunches. Of course, these tips apply to lunch-packing adults, too.

Sources:, LA Times,, TIME