The Earth is home to an estimated 140,000 species of mushrooms, yet only about 10% (approximately 14,000 species) have been identified and named. Mushrooms represent a vast, largely untapped resource for discovering new chemical and pharmaceutical products, particularly polysaccharides with antitumor and immune-stimulating properties. Research on mushroom polysaccharides has been conducted on 651 species and 7 infraspecific taxa from 182 genera of higher Hetero- and Homobasidiomycetes. These polysaccharides are known to prevent cancer development, exhibit direct antitumor activity against various tumor types, and inhibit tumor metastasis. Rather than attacking cancer cells directly, mushroom polysaccharides stimulate the host’s immune system to produce antitumor effects.

These substances are considered biological response modifiers, meaning they: (1) do not harm or add stress to the body; (2) help the body adapt to various environmental and biological stresses; and (3) support the body’s major systems, including the nervous, hormonal, and immune systems, as well as regulatory functions.

Studies have shown that mushroom polysaccharides have no chronic or acute toxicity. Investigations into cell nuclei have found no harmful effects, and DNA analysis has shown no mutations. Additionally, studies on pregnant animals have demonstrated no adverse effects on fetal development, and there has been no observed LD50, a measure of toxicity. Medicinal mushrooms appear to produce no harmful side effects.