Shiitake mushrooms (Lentinula edodes) have been used in Asia for approximately 3 000 years. The mushroom contains an unusually complex number of biovital substances. In addition to the vitamin B group, that is essential for the body but almost never contained in plants - the Shiitake contains Ergosterol (provitamin D) as well as minerals such as potassium, calcium, phosphor, iron and zinc. Seven of the eight amino acids that are essential for humans are also found in Shiitake.

In addition to vitamins and minerals, Shiitake is composed of many organic substances such as nucleotides, amino acids, peptides, organic acids and sugar molecules.