About Medicinal Mushrooms

History and Research

For close to 5,000 years, mushrooms have been consumed for medicinal purposes, documented and published in the earliest Chinese pharmacopoeia Shennong Bencao Jing and Bencao Gangmu (1368-1644AD). In particular, references described the effects as invigorating vital energy, maintaining one’s optimal weight, favoring longevity and avoiding unnecessary aging, if taken appropriately.

Researchers from all fields including western medicine, traditional Chinese medicine and immunology have been investigating some medicinal mushroom’s ability to inhibit tumor growth, alter immune function, exhibit antibacterial and antiviral activity, and thus they have been subjects of research for approximately 50 years. The most researched of the medicinal mushrooms are Coriolus versicolor (Yunzhi, turkey tail mushroom) and Ganoderma lucidium (Lingzhi, reishi).

Selective species of Medicinal Mushrooms

Coriolus versicolor
Ganoderma lucidum Grifola frondosa
Cordyceps

Ganoderma lucidum (língzhī, reishi, mannentake) mushrooms have a long and very well established history in traditional Asian medicine. Ganoderma is the most famous medicinal mushroom in Asia and can be found in many herbal remedies. Ganoderma teas are described in Shennong Ben Cao Jing and Bencao Gangmu. The Ganoderma mushroom is also seen in many ancient Chinese art.

Cellular and animal research has shown Ganoderma may contain anticancer and immune system enhancing properties. Researchers have noted Ganoderma appears to have antibacterial, antiviral, and antifungal properties. Animal studies have noted Ganoderma may protect the live and protect against radiation. A randomized clinical study noted Ganoderma improved urinary tract symptoms in men. Research has shown that Ganoderma contains compounds that may act as ACE inhibitor, inihibit blood platelets, and fibrosis.

Grifola frondosa (Maitake, hen-of-the-woods) is an edible mushroom commonly found on oak trees. The mushroom has long been esteemed in Japan and during feudal times, was worth its weight in silver. In 2009, a systematic review published by the Massachusetts General Hospital, stated randomized controlled trials were warranted to investigate maitake in cases of cancer, diabetes, and for altering the immune response. Maitake may partially inhibit the enzyme cyclooxygenase and aspects of angiogenesis.

Cordyceps (Caterpillar fungus, dong chong xia cao) is an herbal remedy with a long history in China according to a review by the Stanford University of Medicine. The fungus is parasitic to insects. Research has indicated Cordyceps may promote vasodilation, cellular health, have anti-depressant activity, as well as possible anti-cancer activity.

Mushroom Polysaccharides, the immune system and cancer

In western physiology, the immune system guards the body against bacteria, viruses, fungi and toxins and any abnormal cells or any abnormal changes in the cells. Research suggests that serious illness may occur when these abnormal cells escape the immune defense.

Clinical and animal studies suggest medicinal mushrooms may be able to alter the immune response. Compounds in medicinal mushrooms most responsible for up-regulating the immune response, are a diverse class of polysaccharides compounds. According to a 2000 review from Harvard Medical School, “polysaccharide immunomodulators were first discovered over 40 years ago. Although very few have been rigorously studied, recent reports have revealed the mechanism of action and structure-function attributes of some of these molecules. Certain polysaccharide immunomodulators have been identified that have profound effects in the regulation of immune response.”

The potential anticancer effects of medicinal mushrooms are linked to the immune response. Examining the mushroom polysaccharide known as PSK and PSP, the review stated, “the antitumor activity has been evaluated in Japan for prevention of esophageal, gastric, and lung cancer in humans with promising results. In phase II and phase III trials in China, PSP significantly enhanced immune status in 70 to 97% of patients with cancers of the stomach, esophagus, lung, ovary, and cervix. In these studies, PSK and PSP increased the number of immune cells and facilitated dendritic and cytotoxic T-cell infiltration of tumors. The polysaccharides were well-tolerated and compatible with chemotherapy and radiation therapy.”

Refereance on other potential effects and benefits including:

• Effects on blood sugar, cholesterol
  Research has shown that some medicinal mushrooms may have potential to lower elevated blood sugar levels and some mushrooms have been shown to be able to have an inhibitory effect on cholesterol levels.
• In vitro antiviral, antibacterial, antifungal, and antimicrobial activities
  Fungi produce various antiviral, antibacterial, antifungal, and antimicrobial compounds to survive in the wild against competing or pathogenic organisms. These compounds are produced because fungi lack immune systems which protect animals, and lack thick cellulose cell walls which protect plants. The famous antibiotic penicillin and the antifungal drug griseofulvin are both produced from the fungus.
• In vitro anti-hormone activity
  Mushrooms may be able to influence the production of certain human hormones, based on evidence from enzyme assay analysis.
• Antioxidant activity
  Mushrooms are known to contain various types of antioxidant compounds.
• Epidemiological research
  Research in Japan found enokitake mushroom producers had lower cancer rates than the rest of the population. A case-control study published by the International Journal of Cancer in 2009, compared the diets of 1009 women who had been diagnosed with breast cancer with 1009 healthy women. Compared to nonconsumers of mushrooms, women who consumed at least 10 grams of fresh mushrooms per day had a breast cancer risk of only 36%. The risk for those who consumed at least 4 grams of dried mushrooms per day was 53%. A similar case-control study involving 362 women with breast cancer also found a strong association between mushroom consumption and decreased risk of breast cancer in postmenopausal, but not premenopausal, women.