A 4-pound bag of popcorn on sale for $3.69 .That's less than 8 cents per ounce, and an ounce of kernels pops up into a quart of corn. By itself, popcorn is low in calories: 31 per cup for air-popped and up to 55 calories if oil-popped. You can keep it low-cal by going easy on the butter and flavoring it instead with items like garam masala, dill, Italian herbs or onion powder.
