What are they?
Mushrooms have been used for medicinal purposes for thousands of years. Known as nutritional powerhouses, they offer a range of health benefits including immune support, brain health support, anti-inflammatory powers, and anti cancer properties. Although there are a multitude of varieties, research has predominately focused on four main types – reishi, maitake, shiitake and turkey tail.
None of the studies recommend any mushroom extract as a standalone treatment. Instead, researchers have found that these extracts may have benefits for people who use them as an adjunct therapy.
What have they been shown to do?
Studies over this past decade have shown that mushrooms have the ability to stimulate the immune system, modulate cellular immunity, and slow the growth of tumors. Two key compounds, polysaccharopeptide (PSP) and polysaccharide (PSK), have shown to inhibit the growth of cancer cells.
A team of scientists from the Taiwanese research center Academia Sinica, found that F3 polysaccharides, a type of carbohydrate molecule found in reishi mushrooms, can induce antibodies to recognize and kill antigens associated with tumors or cancer cells.
Maitake mushrooms are believed to have similar qualities. In a human trial, conducted by Memorial Sloan–Kettering Cancer Centre in 2009, maitake was shown to stimulate the immune systems of breast cancer patients. Laboratory in vitro research by Sensuke Konno, associate professor of urology at New York Medical College, found that non-toxic concentrations of the GD or PL “fractions” found in maitake mushrooms, when combined with vitamin C, not only reduced growth of bladder cancer cells by 90% in 72 hours, but were also highly effective in killing them.
Perhaps the best known of all the medicinal mushrooms is the shiitake. Not only is it a delicious ingredient, but it is also famed for its compound lentinan. Several papers have found the polysaccharide could help increase the survival rate of cancer patients, including research carried out by a team of scientists at Harbin University, China, in 2008, which found that lentinan was “beneficial in terms of increasing mean survival duration, tumor necrosis and reducing the recurrence rate”.
In China, turkey tail has been used to help prevent and cure liver infections and liver cancer. In Japan, the PSK in Turkey Tail has been approved as a pharmaceutical-grade medicine for cancer treatment and used effectively for more than 30 years. The anti-viral properties of this mushroom may also be used to suppress tumor viruses such as human papillomavirus leading to cervical cancer or hepatitis C leading to liver cancers.
Medicinal mushrooms as an attractive new source of natural compounds for future cancer therapy
Do turkey tail mushrooms benefit health?