Popcorn is a great snack option for people following a low-carb diet because it doesn't contain a lot of carbohydrates. It contains no fat, cholesterol, sodium, or added sugars. Regular corn kernels contain 3.5 g of carbohydrates per cup, while microwaveable varieties have 5 g of carbs per cup so you can enjoy a handful of popcorn without worrying about counting your daily carb allotment.