The Effect of Rinse Water Obtained from the Washing of Rice (YU-SU-RU) as a Hair Treatment

Abstract

We researched the histories of the hairstyles and hair care practices of Japanese women, and found a very close relationship between the two. For example, the court ladies of the Heian Period, whose beautiful long hair, called suberakashi, reached to the floor, were said to have combed their hair each day using Yu-Su-Ru( rinse water obtained from the washing of rice). Rice is considered to be the most important food in the Japanese diet, and the historical fact that rice was used for hair care is very interesting. We therefore focused our attention on the Yu-Su-Ru hair care practice in the Heian Period, and examined its effects on hair. As a result, we found that Yu-Su-Ru exhibited hair care effects, such as reducing surface friction and increasing hair elasticity. However, when hair was treated with Yu-Su-Ru alone, flaking was observed on the hair surface, and the direct application of Yu-Su-Ru was considered difficult. Thus, Yu-Su-Ru extracts, which are highly effective in hair care and do not cause flaking were examined. The results showed that Yu-Su-Ru extracts had multiple functions for hair care at the same time. Thus, the new application of Yu-Su-Ru for hair care was discovered.