Why are Americans so fat? That’s a question explored in a new documentary called “Fed Up.”

Executive producer and narrator Katie Couric discussed the problem with sugar on tonight’s “O’Reilly Factor.”

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Couric said 80 percent of products in the grocery store have added sugar, and many Americans are unaware.

She also noted that some countries are restricting marketing of sugary foods to kids.

“My goal […] is just to make people more aware because I think once they’re educated they can make better choices," she said.

Watch her interview above.

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