Since its beginning until now, the appearance and materials of the futon have changed a lot. During the Heian period (794-1185), the aristocracy used to sleep directly in beds made of tatami. The common people rested at night in more simple piles of straw. 1 In the Edo period (1476-1868), the domestic production of cotton began, and people started using mattresses crafted with this material. Since in this period some people used to sleep with heavy kimono-like quilts, the yogi (夜着) or kaimaki, but without blankets, the word futon meant only mattress.2
Because cotton was not produced in large scale in this time, buying a single futon would be as expensive as buying a luxury car today. It was only after the Meiji period (1868-1912), when Japan started to import cheaper cotton from India and factories made the production process faster and less costly, that futon started to become more affordable for the people in general.2
Still popular today and present in many Japanese households, the futon is an important part of the country's traditional culture and way of life. When walking around Japan during sunny days, it is possible to see many futon being dried in balconies and windows. Japanese people do this to guarantee that the futon will not get contaminated with mold. Nowadays, people can also dry their futon during the rainy season by using futon dryers, electric devices that warm and dry the futon.
Another possible option is purchasing special bed frames that allow air circulation, and prevent the formation of mold. There is a saying in Japanese that the sturdiness of the futon does not let the body turn "soft". This means that the support that the futon offers for the body helps to avoid problems with bad posture and back pain.