Source Naturals, Ahcc 500 mg, 60 CapsulesProduct Overview : Source Naturals, Ahcc 500 mg, 60 Capsules Description: Dietary Supplement Increases Natural Killer Cell Activity AHCC is a proprietary compound produced by cultivation of shiitake mushroom mycelia, grown in rice bran extract. Considered a superfood supplement in Japan, AHCC has been researched extensively for its immune enhancement properties. Preliminary research indicates that AHCC may significantly increase Natural Killer (NK)