Introduction
Mushrooms belong to the fungi kingdom and are distinguished from plants, animals, and bacteria. With countless shapes, sizes, and colors, mushrooms are found in a variety of environments around the world. While some mushrooms are edible and enjoyable, others can be toxic or deadly. Rich in essential nutrients like vitamins, minerals, and antioxidants, mushrooms offer a variety of health benefits. Among these, certain compounds found in mushrooms have caught the attention of researchers for their potential anti-cancer properties.
What Are the Commonly Consumed Mushrooms?
Mushrooms have been traditionally used in Asian and Eastern European countries for their potential role in preventing and treating cancer. Piptoporus betulinus, historically used in Bohemia, was employed for treating rectal cancer and stomach diseases. Inonotus obliquus (Chaga) has been a folk medicine for cancer and stomach issues since the 16th or 17th century.
Commonly consumed mushrooms are:
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Button Mushrooms (Agaricus bisporus) - These are the most common mushrooms found in supermarkets. They have a mild flavor and are often used in salads, stir-fries, and various dishes.
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Shiitake Mushrooms (Lentinula edodes) - Shiitake mushrooms have a rich, savory flavor and are popular in Asian cuisine. They are not only delicious but also believed to have health benefits.
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Portobello Mushrooms - These are mature cremini mushrooms and have a meaty texture. They frequently serve as a vegetarian alternative in dishes, replacing meat.
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Oyster Mushrooms (Pleurotus ostreatus) - Oyster mushrooms have a delicate flavor and a tender texture. They come in various colors and are commonly used in stir-fries and soups.
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Maitake Mushrooms (Grifola frondosa) - Also known as "hen of the woods," maitake mushrooms have a distinct, frilly appearance. They are valued for their potential health benefits and are used in culinary and medicinal contexts.
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Enoki Mushrooms (Flammulina velutipes) - These mushrooms have long, thin stems and small caps. They have a mild flavor and are often used in salads and Asian dishes.
What Are the Benefits of Mushrooms?
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Mushrooms are a good source of essential nutrients. They offer a nutritious option, low in calories and rich in vitamins, minerals, and antioxidants. They contain important nutrients such as B vitamins, vitamin D, selenium, and fiber.
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Some mushrooms are believed to have immune-boosting properties. They contain compounds like beta-glucans that may enhance the immune system.
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Mushrooms contain various antioxidants, including selenium and ergothioneine. These antioxidants aid in free radical neutralization within the body and potentially lower the likelihood of chronic diseases.
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While not as high in protein as animal products, mushrooms contain some protein. They are particularly suitable for individuals following vegetarian or vegan diets.
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Some mushrooms have a long history of utilization in traditional medicine for centuries.
Does Higher Mushroom Consumption Lower the Risk of Cancer?
A study found that higher mushroom consumption is linked to a decreased risk of overall cancer, including both breast and non-breast cancers. Specifically, the risk of total cancer was significantly lower for those with the highest mushroom intake than the lowest. The same pattern was observed for breast cancer and non-breast cancer, indicating a potential protective role of mushrooms in the diet. Among the various cancer types, breast cancer emerges as the most affected by mushroom consumption. Population studies have shown that individuals who regularly include mushrooms in their diet may experience a reduced risk of developing breast, prostate, and colorectal cancers.
What Are the Biological Mechanisms Involved in Mushroom Conception and Incidence of Cancer?
Antioxidant Properties
The potential biological mechanisms supporting the link between mushroom consumption and reduced cancer risk lie in the antioxidant properties of specific mushroom components, including ergothioneine and glutathione. These antioxidants are vital in neutralizing free radicals associated with aging and various diseases, including cancer.
Ergothioneine's Role
Ergothioneine, found in high concentrations in mushrooms, is identified as a sulfur-containing amino acid with robust antioxidant activity. Its potential therapeutic applications extend to reducing the severity of diseases like COVID-19 and is even suggested to be categorized as a "longevity vitamin."
Bioactive Compounds
Besides ergothioneine, mushrooms contain bioactive compounds such as β-glucans, known for their antitumor and immunomodulatory properties. Laboratory experiments demonstrate varying anticarcinogenic effects among mushroom types, emphasizing the potential diversity in their protective mechanisms.
Immune System
A strong immune system is necessary for preventing and controlling cancer. Mushrooms, with their immunomodulatory properties, may play a major role in supporting immune function. Research suggests that certain mushroom extracts can stimulate the function of immune cells, including macrophages and natural killer cells, which are essential for detecting and destroying cancer cells.
Anti-Inflammatory Effects
Persistent inflammation is a crucial element in the onset of various cancer types. Mushrooms have been shown to possess anti-inflammatory properties, potentially reducing the inflammatory processes that contribute to cancer progression. Compounds like triterpenoids in certain mushrooms exhibit anti-inflammatory effects, offering another protection against cancer development.
What Is the Role of Immunomodulators From Mushrooms in Adjuvant Tumor Therapy?
Certain types of mushrooms, like Lentinula edodes, Grifola frondosa, Schizophyllum commune, and Trametes versicolor, contain polysaccharides known for their potential as immunomodulators in tumor therapy. These polysaccharides stimulate the non-specific immune system, demonstrating antitumor activity by activating cells like macrophages, T lymphocytes, and NK cells. The activated cells release cytokines with antiproliferative effects, inducing apoptosis and differentiation in tumor cells.
As adjuvants to major cancer therapies, several mushroom-derived compounds are used in clinical settings, especially in Japan and China. Clinical studies have shown improved survival times, restoration of immunological parameters, and enhanced quality of life in patients receiving these mushroom-derived treatments and standard cancer therapies.
Mode of Application - These immunomodulators can be administered intravenously or orally. For instance, when taken orally, lentinan has shown increased levels of cytokines. Polysaccharides from Ganoderma lucidum, marketed as Ganopoly, have been studied for their palliative effects on cancer-related symptoms in advanced solid cancer patients.
Conclusion
In the quest for natural ways to prevent and combat cancer, mushrooms have emerged as a fascinating study area. Their rich nutritional profile and specific bioactive compounds position them as potential allies in the fight against cancer. While more research is needed to understand the mechanisms at play fully, current evidence suggests that regularly including mushrooms in the diet may contribute to a decreased risk of specific cancer types.
