Grifola frondosa Maitake mushroom is a powerful superfood for the immune system. It is a premier culinary mushroom, 'hen of the woods' has been treasured for thousands of years throughout Asia as an immune boosting, heart healthy and hormone balancing tonic. Extensive scientific research is proving that Maitake extract may be the most effective immune supportive mushroom of all. Maitake mushrooms are one of nature’s richest sources of beta glucan polysaccharides, also known as “biological response modifiers” for their powerful ability to activate the immune system.