Once you start munching on popcorn, you probably won't stop until there's none left. Movie theaters make it worse by serving popcorn in huge tubs, topped with butter, like above left. "Popcorn on it's own isn't bad for you it's a whole grain, it's a fiber," said nutritionist, registered dietician and founder of Nutritious Life, Keri Glassman. "At the movies, they use so much fat and salt that they make it horrible for you." Reduce portion size by popping your own 100-calorie bag and sneaking it into the theater, like the photo on the right. If you're thirsty, water is the best choice. But if you can't enjoy a film without a fizzy drink, switch to diet cola. "In soda, there are so many calories, there's so much sugar, and there are no nutrients," Glassman said. "If you have to have soda, Diet Coke is better than a regular Coke in terms of calories, but it's full of artificial flavors and sweeteners."