Here’s a tip to save both money and calories: Buy the big size and split it. “With the mega-sizing of restaurant meals, sharing is the best way to save money and improve your health at the same time,” says Dayle Hayes, a registered dietitian in Billings, Mont.

For example, at one major fast-food chain, splitting a large order of fries instead of buying two medium-sized ones will save you and your lunch mate 190 calories (90 of them from fat) and about $1.59. And that’s just the fries.

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