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The summer blockbuster season is here and that means millions of Americans will be flocking to movie theaters across the country. And you know what goes hand and hand with the movies – salty, chocolaty and buttery treats that taste great – but are not so good for your waistline.

“A large popcorn with butter is not one of your best choices,” Pam O’Brien, executive editor of “Fitness” magazine told FOXNews.com. “It’s 1,220 calories. [Women] are supposed to eat around 2,000 calories a day, and if you get that large popcorn — you’re using more than half of your calories for the day. So it’s pretty astonishing.”

And don’t be fooled by the combo deals, O’Brien said.

“When you’re deciding what to get, and you see the price difference between the large and jumbo is only 75 cents, don’t upgrade,” she said. “It’s 1,640 calories for a jumbo, and that’s a lot!”

PHOTOS: Click here to see the best and worst movie snacks.

Other diet-busting snacks include:

— A jumbo-sized Snickers bar comes in at more than 500 calories;

— A 6.75-ounce bag of Reese’s Pieces has 935 calories;

— A large bag of M&M’s contains 750 calories;

— A jumbo bag of Skittles packs nearly 800 calories.

“So again, you’re eating hundreds and hundreds of calories,” O’Brien said.

But not all the news is bad. There are some classic movie snacks that are perfectly healthy to eat.

“Junior Mints are a good option,” O’Brien said.

A theater-size box of the minty treat, which has more than three servings, is just under 600 calories and they’re low in fat as well. Gummy Bears are another healthier choice, and if you still need your chocolate fix, grab a box of Milk Duds.

The bottom-line: Skip the popcorn and opt for a soft pretzel instead. The salty treat has 483 calories compared to the 1,220 calories in a large popcorn. And you can even add a little bit of mustard to it. The condiment is low in fat and calories.

One last piece of advice: Avoid the large soda and grab a bottle of water instead — it’s the single healthiest item you’ll find at a movie theater, according to O'Brien.

Click here to read more from Fitness magazine.