Reported by Lisa Bell

Have you heard about foods that have negative calories, like celery? Well guess what? There aren't any, sorry.

For people trying to lose weight fast, one diet that was popular for a while was the negative calorie diet that claimed you could lose weight by eating food with no calories -- foods that used more calories to digest than they contain, such as celery.

Well, the experts say that's really not the way it works.

Researchers say foods that are low in calories and high in fiber -- that take a while to digest -- are still great for losing weight. These foods include apples, carrots, broccoli and lettuce.

But as for that "negative calorie" celery? Enjoy it if you want, but think about this -- you would have to eat 350 stalks of it to lose just one pound.

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