"Popcorn counts as being a whole grain, so it's actually pretty healthy for you," says Zannat Reza, a registered dietitian based in Toronto. But we're not talking about movie-style popcorn that's drenched in butter.  Keep it plain or add healthier toppings such as Parmesan cheese or a pinch of brown sugar and cinnamon. "If you're adding [the topping] yourself, you have a lot more control over how much you put on," Reza says.