Agaricus originates from Brazil; it has been discovered only 30 years ago and has been commercially cultivated in Asia and South America since 1993.

Its most important compounds include vitamin B1, B2 and a group of polysaccharides (complex sugars) believed to be the compounds responsible for its immune-boosting effects. All known medicinal mushrooms contain polysaccharides, however, Agaricus contains the highest amount. After several successful clinical trials theses substances have been used as an immune adjuvant in the treatment of HIV patients in the US; in Japan, they are widely used in cancer therapy.
The polysaccharides activate the immune system and thereby increase the production of interleukin-1, which indirectly functions to destroy or prevent the proliferation of cancer cells. In addition, natural killer cells, which attack infected cells and possible cancerous cells and destroy bacteria as well as viruses, are activated.