One cup of air popped popcorn has 31 calories! Now that is a light but filling snack. If you don’t have a hot air popper machine, just cook it in a pot with some oil (to cover the pan) and a touch of salt. When the oil is hot add the corn (about 1/2 cup) and cover with the lid. When you hear the “pops” start, begin shaking the pot. I usually lower the heat, so that I don’t burn the popcorn. Then, slowly open the lid. Instead of salt, you can add paprika, chili powder, or garlic powder.
Source: USDA nutrition database.