Juglans regia is a deciduous tree native to the mountain areas of Central Asia. It was introduced to East Asia and Europe several thousands of years ago and widely cultivated as an ornamental tree as well as for its nuts. The seeds of J. regia, also known as walnut, are edible, and used as highly nutritious food. Walnut has long been known for various pharmacological activities therefore used as folk medicine for treating diverse symptoms. In Traditional Korean Medicine, walnut is known to be good for hair and skin care, also for asthma, diabetes, inflammation and skin diseases.

Walnut contains polyphenols, unsaturated fatty acids such as alpha linolenic acid and linoleic acid, essential amino acids, and minerals. The most abundant flavonoid in walnut is quercetin that exhibits anti-oxidant and anti-inflammatory activities. According to the scientific researches, walnut has skin protective effect by down regulating the inflammatory response and anti-oxidant effect due to its polyphenolic compounds.