Mushrooms as Food and Medicine – The Fantastic Fungi World

We have written several posts where we highlight the health benefits of eating mushrooms, especially when it comes to cancer: Anti-Cancer Foods, Top Foods to Fight Inflammation and 5 Foods to Boost Your Immune System. Today we will dive into some of the most common commercially available mushrooms, especially those known for their medicinal, anticancer, and anti-tumorigenesis properties.

Mushrooms are not plants; they are so diverse and unique that they belong to a kingdom by themselves: the fungi kingdom. There are over 2000 species of mushrooms in nature, and over 25 species are commercially cultivated and consumed by humans, being widely accepted as functional foods¹. Let’s get an overview of the overall nutritional value, important bioactive compounds, and health benefits of mushrooms.

Mushrooms as Food and Medicine

Mushrooms have been consumed worldwide and are an integral part of many cultures, both as food and medicine. They are considered functional foods because they provide basic nutrition and health benefits and help reduce the risk of chronic diseases like cancer. Mushrooms also possess a unique taste and subtle flavor, playing a significant role in a healthy and balanced diet. Mushrooms are low in calories, carbohydrates, sodium, and fats and are cholesterol-free¹. Numerous studies have highlighted the potent bioactive compounds in edible mushrooms, including phytochemicals (alkaloids, phenolic acids, flavonoids, carotenoids), fiber, polysaccharides, selenium, vitamins, and the crucial antioxidants ergothioneine and glutathione, which may play a significant role in the prevention of cancer¹.

Nutrition and Bioactive Compounds

Mushrooms are a rich source of many nutrients, with myriad health benefits and mechanisms of action, supporting the immune system being one of the most important.

Vitamins and Minerals

Mushrooms are a unique source of essential vitamins (e.g., thiamin (B-1), riboflavin (B-2), niacin (B-3), pyridoxine (B-6), ascorbic acid (C), vitamin D, vitamin E, and other B vitamins) and minerals, such as^1,2,3:

• Selenium – helps the body make antioxidant enzymes to prevent cell damage. Cremini or portobello mushrooms will provide more benefits.
• Vitamin D – supports cell growth, enhances immune function, and reduces inflammation. Maitake mushrooms are one of the best options to add vitamin D to your diet. Mushrooms are the only food source of vitamin D.
• Vitamin B6 – essential for the formation of red blood cells, proteins, and DNA. The best source of vitamin B6 are Shiitake mushrooms.
• Vitamin B1, B2, and B3 – B vitamins are essential for energy production and the metabolism of fats and proteins. They also contribute to a healthy liver and nervous system and skin, hair, and eye health. Shiitake, portobello, and oyster mushrooms are good sources of these vitamins.

Bioactive compounds in mushrooms

Mushrooms contain bioactive compounds potentially protective against cancer. These bioactive compounds include polysaccharides (e.g., α- and β-glucan, proteins (e.g., fungal immunomodulatory proteins, ribosome-inactivating proteins), fatty acids, ash, glycosides, alkaloids, volatile oils, tocopherols, phenolics, flavonoids, carotenoids, folates, ascorbic acid enzymes, and organic acids, among other. Considering the immunomodulatory and anti-tumor effects, glucans and specific proteins are responsible for most of the biological effects of mushrooms^4,5,6,7.

A study published in the International Journal of Molecular Sciences in 2021, entitled “Medicinal Mushrooms: Bioactive Compounds, Use, and Clinical Trials, detailed the importance of some of these bioactive compounds⁵.”

• Polysaccharides – structural components of the mushroom cell wall^5,7
• Best-known and most potent mushroom-derived substances with anti-tumor and immunomodulating properties.
• Primarily responsible for immunomodulatory effects due to their ability to bind to specific cell wall receptors and stimulate specific immune responses.
• Also have a strong ability to carry biological information.
• Characterized by antitumor, immunomodulatory, antioxidant, anti-inflammatory, antimicrobial, and antidiabetic activity.
• Best known and most abundant are α- and β-glucans. β-glucan is the most versatile metabolite due to its broad-spectrum biological activity.
• Heteroglycans, peptidoglycans, and polysaccharide-protein complexes also contribute to the biological activity of mushrooms.

• Terpenes⁵
• Some of the most important constituents of functional or medicinal mushrooms.
• Modulate the immune system by stimulating the expression of genes coding for proteins involved in the immune response.
• Exhibit anti-inflammatory, antioxidant, and antitumor properties.
• High terpenoid contents are found in mushrooms belonging to the genus Ganoderma, the most popular species being Ganoderma lucidum (reishi).

• Mushroom Proteins⁵
• Mushroom protein possesses cytotoxic and anticancer properties.
• Some of these proteins have a characteristic and marked immunomodulatory effect, the fungal immunomodulatory proteins).
• Mushroom proteins also include lectins, which are involved in many biological activities, such as innate immunity and cell-to-cell interaction.
• Lectins also show immunomodulatory, antitumor, and antiproliferative properties.

• Other Bioactive Compounds⁵
• Phenolic compounds.
• Antioxidants with different mechanisms of action (oxygen scavenging, metal inactivation, free radical inhibition, peroxidase decomposition).
• Laccases (copper-containing oxidases).
• Fatty acids.

Mushrooms Health Benefits

We use medicinal mushrooms at An Oasis of Healing and try to incorporate them into our foods as much as possible because they have been shown to have diverse and potent health benefits. Mushrooms exhibit more than 100 medicinal functions and a broad spectrum of pharmacological activities, including anti allergic, antibacterial, antifungal, anti-inflammatory, antioxidative, antiviral, cytotoxic, immunomodulating, anti-depressive, antihyperlipidemic, antidiabetic, digestive, hepatoprotective, neuroprotective, nephroprotective, osteoprotective, and hypotensive activities^2,5.

Top Health Benefits of Mushrooms

• Enhance immunity
• Decrease the risk of cancer
• Exhibit antitumor, anti-inflammatory, and antiallergic properties
• Increase antioxidant activity
• Manage blood sugar and cholesterol levels
• Beneficial for gut microbiota
• Improve cognition and brain health
• Source of vitamin D
• Many More…

In what relates to cancer risk, a 2021 Systematic Review and Meta-Analysis of cancer studies found that higher mushroom consumption was associated with a lower risk of cancer. The study showed that eating just 18 grams of mushrooms daily was associated with a 45% lower risk of total cancer when compared to an intake of 0 grams daily. And 18 grams is equivalent to about only 1/8 cup or two medium mushrooms daily¹!

More important than trying to find “the best” mushroom to eat is to eat the mushrooms that you like and enjoy so that you actually eat them! Because any variety of mushrooms, when incorporated into your daily diet, will contribute to your health and longevity and lower the risk of cancer and other chronic illnesses.

References

1. Ba DM, Ssentongo P, Beelman RB, Muscat J, Gao X, Richie JP. Higher Mushroom Consumption Is Associated with Lower Risk of Cancer: A Systematic Review and Meta-Analysis of Observational Studies. Adv Nutr. 2021 Oct 1;12(5):1691-1704. doi: 10.1093/advances/nmab015. PMID: 33724299; PMCID: PMC8483951.
2. Valverde ME, Hernández-Pérez T, Paredes-López O. Edible mushrooms: improving human health and promoting quality life. Int J Microbiol. 2015;2015:376387. doi: 10.1155/2015/376387. Epub 2015 Jan 20. PMID: 25685150; PMCID: PMC4320875.
3. UCLA Health. 7 health benefits of mushrooms. Jan 24, 2022. https://connect.uclahealth.org/2022/01/24/7-health-benefits-of-mushrooms/, accessed Nov 2, 2022.
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5. Venturella G, Ferraro V, Cirlincione F, Gargano ML. Medicinal Mushrooms: Bioactive Compounds, Use, and Clinical Trials. Int J Mol Sci. 2021 Jan 10;22(2):634. doi: 10.3390/ijms22020634. PMID: 33435246; PMCID: PMC7826851.
6. Yadav SK, Ir R, Jeewon R, Doble M, Hyde KD, Kaliappan I, Jeyaraman R, Reddi RN, Krishnan J, Li M, Durairajan SSK. A Mechanistic Review on Medicinal Mushrooms-Derived Bioactive Compounds: Potential Mycotherapy Candidates for Alleviating Neurological Disorders. Planta Med. 2020 Nov;86(16):1161-1175. doi: 10.1055/a-1177-4834. Epub 2020 Jul 14. PMID: 32663897.
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8. Ganesan N, Baskaran R, Velmurugan BK, Thanh NC. Antrodia cinnamomea-An updated minireview of its bioactive components and biological activity. J Food Biochem. 2019 Aug;43(8):e12936. doi: 10.1111/jfbc.12936. Epub 2019 Jun 4. PMID: 31368557.
9. Robinson, B., Winans, K., Kendall, A. et al. A life cycle assessment of Agaricus bisporus mushroom production in the USA. Int J Life Cycle Assess 24, 456–467 (2019). https://doi.org/10.1007/s11367-018-1456-6
10. Das G, Shin HS, Leyva-Gómez G, Prado-Audelo MLD, Cortes H, Singh YD, Panda MK, Mishra AP, Nigam M, Saklani S, Chaturi PK, Martorell M, Cruz-Martins N, Sharma V, Garg N, Sharma R, Patra JK. Cordyceps spp.: A Review on Its Immune-Stimulatory and Other Biological Potentials. Front Pharmacol. 2021 Feb 8;11:602364. doi: 10.3389/fphar.2020.602364. PMID: 33628175; PMCID: PMC7898063.
11. Ashraf SA, Elkhalifa AEO, Siddiqui AJ, Patel M, Awadelkareem AM, Snoussi M, Ashraf MS, Adnan M, Hadi S. Cordycepin for Health and Wellbeing: A Potent Bioactive Metabolite of an Entomopathogenic CordycepsMedicinal Fungus and Its Nutraceutical and Therapeutic Potential. Molecules. 2020 Jun 12;25(12):2735. doi: 10.3390/molecules25122735. PMID: 32545666; PMCID: PMC7356751.
12. Lu Y, Jia Y, Xue Z, Li N, Liu J, Chen H. Recent Developments in Inonotus obliquus (Chaga mushroom) Polysaccharides: Isolation, Structural Characteristics, Biological Activities and Application. Polymers (Basel). 2021 Apr 29;13(9):1441. doi: 10.3390/polym13091441. PMID: 33947037; PMCID: PMC8124789.
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