Medicinal mushrooms – Could including mushrooms into your diet help to fight cancer?

Mushrooms have been part of our diet for thousands of years and the medicinal properties of mushrooms have been recognized by Eastern medicine practitioners for many years. Studies in China, Korea and Japan have looked at some of the healing properties of mushrooms. ‘Current evidence primarily focuses on the value of using mushroom supplements as a complementary treatment for cancer and as an immunostimulant’.

The cell walls of mushrooms are made up of complex sugars that have a number of biologically active properties. Beta-glucans (a polysaccharide), has been shown to modulate immune function, suppress the growth of tumor blood vessels, and inhibit tumor growth. The amount of beta-glucans available in mushrooms can vary, and this seems to be influenced by the life-stage of the mushroom more than the actual variety of mushroom.

There has been more and more interest in the anti-cancer properties of beta-glucans. Studies show that beta-glucans in mushrooms modulate the growth of tumor blood vessels (angiogenesis), which is a critical process in the development of cancer. In a study done on mice that were treated with polysaccharides from mushrooms, it was shown that they had ‘smaller tumors, fewer tumor blood vessels, and suppression of a key angiogenesis-stimulating protein, called vascular endothelial growth factor (VEGF).’ There have been some small studies done in humans with advanced cancers and they showed some signs of slower deterioration, improved symptoms, and enhanced immune activity.

Mushrooms are part of the fungi kingdom and are low in fat and calories and high in protein. They also contain micro-nutrients such as thiamine, riboflavin, niacin, vitamin C, phosphorus, and potassium. These days medicinal mushrooms are generally grown commercially and are available dried or in liquid extract and capsule form.

Promising Medicinal Mushrooms

Reishi mushroom (Ganoderma lucidum) “mushroom of immortality”

  • Large woody mushroom, deep red in color.
  • Inedible – bitter taste and woody texture.
  • In-vitro and animal studies – reishi supplements may have chemo-protective effects, alleviate chemotherapy-induced nausea, and can increase the efficacy of radiotherapy (Memorial Sloan-Kettering Cancer Center).
  • Potential side effects:
    • Dryness of the mouth, throat, and nasal area, itchiness; stomach upset; nosebleeds; and bloody stools.
    • May interfere with anti-hypertensive and anticoagulant treatment.

Maitake (Grifola frondosa) – “hen of the woods”:

  • Grow in large clusters that resemble a hen’s tail feathers.
  • Maitake D-fraction extract supplement could enhance the immune system, inhibit tumor growth and prevent the development of cancer in normal cells.
  • Key component of the mushroom is beta-glucan.
  • Only animal studies done
  • Side effects:
    • Not a lot of information
    • May interfere with antidiabetic drugs

 White button mushroom (Agaricus bisporus) – Crimini:

  • DId you know when Button mushrooms are fully matured, they grow to become Portobello mushrooms.
  • Recently reported to play a role in cancer management.
  • Phytochemicals in the mushroom block the activity of the aromatase enzyme, which decreases the production of estrogen – may help control and possibly prevent the growth of hormone-dependent breast cancer cells. (Researchers from City of Hope)
  • Currently in the early stages of evaluating the effects of white button mushroom extract on estrogen levels of postmenopausal breast cancer survivors.
  • Also found to block the conversion of the enzyme steroid 5-alpha-reductase to dihydrotestosterone – associated with an increased risk in the development of prostate cancer.
  • White button mushroom extract appears to be safe for most people when taken for up to 12 weeks.
  • Side effects:
    • May cause hypoglycemia in some diabetics
    • Itching.
    • Reports of liver toxicity in people who took white button mushroom extract during cancer treatment.

 

At the moment, more research needs to be done on humans with regards to the beneficial effects of mushrooms. As with any supplement, it is always best to first speak to your doctor or health care professional before starting on any new supplement.

Wanting to add more mushrooms into your diet, check out our delicious stuffed mushroom recipe: Click here

Munchwize Dietitians are based in Cape Town, in Claremont.

 

References:

  1. Ilkay, J. Medicinal Mushrooms. Today’s Dietitian. 2011. Vol. 13 No. 9 P. 30
    Smith, R.Edible Mushrooms Have Antiangiogenic and Tumor-Fighting Properties
  2. Akramiene D, et al. Effect of beta-glucans on the immune system. Medicina (Kaunas) 2007;43(8):597-606.
  3. Manzi P, et al. Commercial mushrooms: nutritional quality and effect of cooking. Food Chem 2004;84:201-206.