One of the best medicinal ingredients used by people in the Asian continent is Shiitake Mushrooms. The shiitake mushrooms are grown with fewer nutrients (in sawdust rather than logs). These are commonly available in the supermarkets nowadays.
Many experts suggest getting proper doses of the vitamin through the shiitake mushroom (grown under the sunlight). Many of us can't resist without the superior taste of this mushroom that remains highest in demand in Japan. In the Japanese supermarkets, the cost of one pound shiitake mushroom starts with 40 USD.