For example, instead of munching on a handful of potato chips, you can fill up on three handfuls of air-popped popcorn for the same number of calories.

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"My kids also love it on air-popped popcorn, " says Beller.

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Other near-perfect snacks are carrot sticks and hummus, low-fat or air-popped popcorn sprinkled with parmesan cheese, cantaloupe melon wedges wrapped in smoked salmon and low-fat cheese on whole-grain crackers.

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For example, if you eat when you are stressed, try to choose foods that are very low-calorie density like air popped popcorn or vegetables and hummus to keep calories under control.

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