Harvested when the kernels are hard and dry. Popcorn was originally made in clay pots filled with heated sand as recorded in the journals of 17th-century French explorers. The explorers observed this practice in the Iroquois tribes of the Great Lakes region.
Popcorn is a good source of dietary fiber and manganese. It is a source of protein and zinc, as well as magnesium and phosphorus. It has trace amounts of B-complex vitamins, iron, potassium, copper, and folate. Popcorn is considered a low-calorie, low-glycemic food.