(We are close, but we are not there yet)
Essays and Analysis

By Dianna Smith
Chair of the Medicinal Fungi Committee, NAMA
NOTE: The opinions expressed here are those of the author, and are not to be construed as medical advice by the author, McIlvainea or NAMA.


The following essay aims to determine the utility of using macro fungi as medicine based on current research. Views regarding the efficacy of macro fungi to prevent and or cure diseases cover a broad spectrum between those who are convinced that they are efficacious based on observational, anecdotal, or testimonial evidence and those who might be convinced of their effectiveness if there was incontrovertible, repeatable, science-based evidence indicating that they work. My own opinions have waivered back and forth somewhat since beginning to write this multi-part essay about a year ago. The more I read, the more I realize how complicated we humans are in every respect conceivable. My intent in this multi-part essay is to evaluate arguments for and against the use of mushrooms as medicine. I am also interested in examining the deeper social, historical and cultural motivations behind supporting or rejecting their use for the prevention and cure of the diseases associated with aging: cancers, heart diseases, diabetes, Alzheimer’s and Parkinson’s diseases. While I am not a medical doctor, various versions of this paper have been scrutinized by physicians associated with NAMA, including the illustrious members of NAMA’s Medicinal Fungi committee.1 Any errors in content, however, are my own.


The most reliable information on medical fungi is to be found in peer-reviewed science journals. A number of these are open-access articles available online through the National Institutes of Health website, Unfortunately, few of us can readily consult the majority of research articles on the topic beyond reading the initial abstract unless we are subscribers or have access connections with a university or other professional. A great majority of studies on medicinal fungi are written in Chinese, Japanese or Korean and have not been translated into English. This puts inquiring amateurs at a disadvantage. Few of us, in any case, have the educational background to interpret and understand the chemistry, genetic concepts, and medical language used to describe strengths or weaknesses of existing clinical trials on fungal medicines. It is far easier for mycophiles to find articles and studies about medicinal fungi in non-peer-reviewed journals, where standards of testing are generally of poorer quality and are written by researchers connected with or hired by manufacturers of fungal products. These are primarily geared toward the physically active, health-aware, and educated young families, nutritionists as well as practitioners of professional alternative medicines and methodologies. Other sources of information include health and wellness magazines,2 television,3 news articles and vitamin, mineral, herbal and fungal supplement sales websites. The nature of much of the readily available information unfortunately generally lacks reference to reliable scientific studies to back up the sensational preventative and curative claims being made for medicinal fungi. Absence of solid evidence showing that fungi used medicinally have both preventative and curative advantages has not stopped many of us from jumping to the conclusion that what happens in a Petri dish, in lab rodents or more rarely in a small group of hospitalized human subjects will also occur for the majority of us. As we shall see when examining the most popular fungal medicinals, many studies are tantalizingly suggestive that they may prove useful in certain situations, but additional testing using standard protocols needs to be conducted to ascertain their effectiveness in the complex environment of the human body. Some entrepreneurs and supplement companies have nevertheless piled onto the elixir bandwagon and suggest the use of fungal supplements may have efficacy for every imaginable disorder.

Fungal and herbal medicines currently fall into the category of ‘dietary supplements.’ Thanks to the lobbying efforts of vitamin companies looking out for their own business interests under the guise of protecting the public’s right to decide for themselves what is good for them, these are loosely regulated by the FDA. Makers of supplements do not have to prove their products are safe or effective. Retailers can say just about anything they want regarding the efficacy of their health products under the guise of providing educational heath information as long as they include a disclaimer "This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease;" or "These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease."4 This is often at the bottom of a website page or bottle in unreadable, tiny print. One result of the lack of laws designed to protect consumers rather than manufacturers is that in New York, Connecticut and Indiana tests of store brand supplements revealed that four out of five herbal supplements sold have been found to not have the ingredients listed on their labels.Furthermore analysis of numerous fungal supplements has found that they vary tremendously in the amount of medicinal ingredients included which are believed to be important agents of healing depending on whether or not they are powders derived from grain grown mycelium or water-soluble, alcohol extracts or dual extracts from whole fruiting bodies.6

There are also a host of popular books available devoted to broadcasting the real and/or potentially remarkable health benefits of mushrooms. The Amazon book department has no less than 14 pages listing publications on the topic. Some of the best books on the subject have even been written by NAMA members. A personal favorite is by Robert Rogers, author of The Fungal Pharmacy7 along with other books as well as articles published in issues of Fungi Magazine and Mushroom the Journal. The expansion of the medicinal mushroom market has also been bolstered by the writings of Dr. Denis Benjamin: Mushrooms: Poisons and Panaceas and Musings of a Mushroom Hunter: A Natural History of Foraging.8 Also influential and frequently quoted on Wikipedia and elsewhere is Christopher Hobbs, author of Medicinal Mushroom9, Greg Marley’s Mushrooms for Health: Medicinal Secrets of Northeastern Fungi,10 and the YouTube TED talks of Fungi Perfecti’s founder and president, Paul Stamets. His books, including Mycelium Running: How Mushrooms Can Save the World (2005),11 have inspired the creation and growth of medicinal fungi research at American universities as well as numerous Citizen Science projects, such as those involving the use of fungi to solve difficult environmental12 and health problems.13

Interest in mushrooming and in medicinal fungi in particular is also expanding through the nearly ubiquitous role of the Internet and social media in our lives. ‘Google’ the term ‘medicinal mushrooms’. At least 56 pages listing numerous books, articles and products devoted to the general subject will pop up on your computer screen. Another source of information to fungiphiles are social media websites like Facebook where many inexperienced mushroomers go to ask questions about identifying a fungus, its edibility and its medicinal properties. In addition to its numerous mushroom identification groups, Facebook hosts at least 15 different North American groups devoted solely to medicinal fungi. Here is a sampling of some of the sites I have been monitoring over the past three years: Alternative Cancer Therapies, Chaga Mushrooms, Chaga Vermont, Chaga Canada, Chaga Tea, Chinese Medicine and Natural Health Research, Good Medicine (mushrooms), Medicinal Mushrooms, Medicinal Mushrooms and Supplements, Medicinal Mushroom Products, Medicinal Mushrooms for Improved Health, Trametes versicolor and Other Medicinal Mushrooms, and International Society for Medicinal Mushrooms. New fungiphiles are posting their photos and asking group members, “What is the name of this fungus. Is it medicinal?” Currently, the latter question seems to have supplanted “Is it edible?” in pervasiveness. On receiving confirmation that the person has indeed found a potent macro-fungal medicine, the next question is typically “How do I turn this into a medicine that I can take as a tonic, therapeutic tea or pill?” “Oh, and what does this medicine do for my state of health?”

What diseases are medicinal mushrooms used for and what is the level of evidence available to confirm we can safely take them to assist us in preventing and curing these diseases? What dosages are effective and for how long? Can medicinal mushrooms safely be taken along with herbal and/or conventional medicines? What is the quality of current information on medicinal mushrooms? Can all of it be trusted?

To find answers to these and related questions, I have been reading peer-reviewed and non-peer-reviewed literature which purportedly demonstrates the apparent effectiveness of medicinal fungi that have received the most attention. Two disparate concepts are discussed and sometimes incorrectly conflated. Fungal compounds and their secondary metabolites are believed to act as immune system modulators, strengthening the defense mechanisms of the immune system. Secondly, fungal compounds may act as free radical scavengers. Free radicals are highly reactive molecules that will react with any available biomolecule, such as DNA or an enzyme. Free radical scavengers are, therefore, sacrificial molecules that react with the free radical, protecting the essential cellular components and preventing cellular damage. These two protective features are cited by proponents of employing macro-fungi for both prevention and cure of diseases to explain what they are doing in the body of the healthy and the ill. I have informed myself about problematic ‘modern’ diseases many of us are facing or may face in the future: diabetes, heart diseases, Alzheimer’s and especially cancers. Many mycophiles are convinced that this seemingly growing constellation of diseases can be prevented, as well as painlessly and inexpensively treated and even cured using ‘natural’ medicinal fungi that have purportedly been effectively used in China and elsewhere for many thousands of years.

Belief in the efficacy of fungal medicinals owes a lot to acceptance of the early conclusions reached by twentieth century Asian researchers’ efforts to prove they work to prevent and cure the diseases described in pre-modern medical texts as well as those described by modern biomedicine. They also sought proof of their efficacy to modulate the course of a plethora of other health conditions common among aging populations of the world. Modern Asian research on fungal medicinals is gradually becoming more ‘scientific’ and claims of their ability to cure, if not prevent diseases, more tempered. But like many western proponents of employing medicinal fungi for disease prevention and cure, pharmaceutical researchers, who are advocates of what is known as Traditional Chinese Medicine (TCM) believe they may hold the keys which will unlock the secrets of long life. It is also hoped that the F.D.A. will soon be convinced and accept the veracity of their medicinal value and permit their complex herbal tonics and formulas to be sold in the U.S. as prescription grade medicines. I claim no expertise in this absorbing and complicated subject. Nevertheless, I believe I can offer everyone an overall perspective that is illuminating with respect to the medicinal fungi now being studied and the diseases for which they are recommended to prevent, modify or cure.

Advocates for using medicinal fungi throughout the world are impressed by allegedly ancient use in Asian cultures, which were influenced by the medical theories, practices and remedies of Confucian scholar-physicians over the course of several millennia. I would like to suggest that most of us who are proponents of employing fungi medicinally have an optimistic but severely distorted view of the historical use of fungi in China, of the conditions for which they were used, of the efficacy of pre-modern Chinese medicine in general and the goals of its various kinds of practitioners. Duration and antiquity of use, including the government health and pharmaceutical authorities and researchers of TCM, appear to imply proof of efficacy for many of us. Where is the evidence that fungal medicinals have been successfully used from ancestral times through the present for the diseases we are increasingly experiencing as we age? Where is the proof that they worked? On the following sections we will explore both the Western and the Asian concepts of health and disease and the criteria each uses to justify their continued employment.

Lest you assume I am a complete novice on this subject, I should reveal that I am a ‘lapsed’ historian of science. My graduate research course work and thesis at Tufts, Harvard, and M.I.T. were in the comparative history of science and technology in pre-modern China and the West. I studied under the guidance of mentor Nathan Sivin,14 foremost historian of the Chinese sciences of astronomy, alchemy and medicine in the past and in modern times. That was 40 years ago. Much has been published on these topics in the years that have elapsed since departing graduate school. Sivin and subsequent generations of his doctoral students have published hundreds of erudite journal articles and books covering roughly 2,000 years of Chinese medical theories, literature on diseases, pharmaceuticals, and practices. Becoming the most recent Chair of the Medicinal Fungi Committee has given me a unique opportunity to update my knowledge of Chinese medical practices especially with regard to fungi throughout Chinese history and wherever classical Chinese medicine has taken hold as an alternative or integrative system of ideas, pharmacology and healing methodologies.

I have immersed myself in several of the more influential of over 10,000 pre-twentieth century Chinese medical texts, treatises on diseases, prescriptions, medical ethics, and therapies covering roughly 2,500 years or so of historical changes. Few proponents of using medicinal fungi have the language training to translate and understand the esoteric, varied and often contradictory medical theories and practices described in pre-modern Chinese medical literature. Most writers and even researchers have simply accepted and repeated the results of initial studies on the medicinal effects of fungi. They espouse the often-inaccurate statements released by Chinese government authorities regarding the superiority of so-called TCM in addressing illnesses for which modern biomedicine is allegedly unable to provide definitive cures.

I have also explored the social and political tensions experienced in twentieth century China between physicians trained in modernized Taoist, Legalist, or Confucian-inspired classical medical thought and practices and the proponents of modern conventional medicine. Government decisions to favor one over the other in order to affordably care for a large rural population, and to build support and acceptability of TCM by the Chinese, and to set the stage for advancing China’s role in creating an international medicine incorporating the best of both ancient and modern drugs and therapies and advancing the use of TCM throughout the world. Coincidentally, interest in both fungal and herbal medicines and medical practices used historically in various cultures took off in Europe and the Americas at roughly the same time.

The two-word term ‘medicinal fungi’ as used in this essay refers to fungi that both historically and contemporaneously have been employed by healers and their patients to treat human experiences of illness or wellness in many of the world’s cultural heritages. The term is often presumed to imply that ‘medicinal fungi’ are universally or even mostly effective as preventative and/or curative of diseases. Fungi have been employed by various healers, usually as one ingredient in combination with many others in prescriptions and restorative rituals. It does not follow that they are preventative or curative of the diseases for which they have been or are now being employed unless there is evidence that determines their efficacy. Some of us, however, have assumed that the medical practitioners in the past employed natural medicines to prevent and cure diseases common in the present based on empirical evidence accumulated and verified through the millennia to work gently and successfully on their patients.

Currently, there is also no satisfactory consensus yet about which of the hundreds or even thousands of fungal compounds are most effective for particular disease conditions, or which shouldn’t be used and why. There is evidence that fungal metabolites have the ability to ‘immunomodulate’. The popular literature has distorted this property of fungal metabolites into the notion that fungi ‘know’ whether to enhance or suppress immune responses as needed to restore the body to a state of health. Studies suggest that the immune system is a great deal more complicated than presumed. We don’t know the optimal dosages to be given to healthy volunteers for prevention or to sick patients for purposes of relieving them of some of the normal body responses (discomforts) to cytotoxic drugs. Cultivators the world over are still trying the figure out the best substrates on which to grow the mycelia of the medicinal mushrooms currently being studied.

Nevertheless, research conducted in Asian countries, where they are employed both as therapeutic foods (nutraceuticals) and as medicine along with conventional biomedicine, suggest they may be useful for preventing and curing the legion of diseases that afflict humans. Optimists among us have jumped to the conclusion that they are efficacious based on the reported results of a limited number of nonhuman trials. Limited data has not dissuaded advocates from declaring that:

Science is now showing that medical mushrooms are capable of slowing aging, improving blood flow, reducing the risk of heart disease, improving your skin and hair, stabilizing cholesterol and blood sugar, protecting the kidneys and liver, improving respiratory function, decreasing platelet aggregation, increasing sexual function and athletic ability. Mushrooms with anti-tumor activity appear to increase the number and activity of killer T and natural killer (NK) lymphocytes, with no toxicity to healthy cells. They also have potent antiviral (including HIV), antibacterial, antifungal, anti-inflammatory and anti-tumor properties.15

China’s motivation for disseminating its cleaned-up versions of TCM throughout the world as a complementary practice, is tied up with its hope to sell its patented medicines overseas. Arguments for the efficacy of medicinal fungi in China and elsewhere have been based on reference to its purported antiquity and duration of use, and not on firm scientific evidence. I aim to show that much of the information regarding the historical use of particular fungal medicinals to cure specific diseases, including cancers, is inaccurate, incomplete, and appears to be based more on wishful thinking rather than facts. This does not mean that further scientific research should not be pursued on these products. All of the world’s folk medicines need to be studied to learn whether or not they can serve as useful potential drugs.

My educational background, coupled with extensive recent exploration of literature on the history of disease theories, pharmaceutical testing standards and protocols, and medical practices in ancient and modern times, affords me a unique perspective from which to consider the current state of affairs with respect to questions related to the efficacy of medicinal fungi. I am convinced that this background is critically important for understanding the widespread influence of TCM, and the rationales for adopting and incorporating the majority of favored and researched fungal medicinals into our dietary and health practices.

The fact is, the scientific study of humans, their interdependent beneficial and pathogenic microbes, viruses, immune functions, their illnesses and knowledge of the chemistry and interaction of plant and animal compounds with our health is still in its infancy. This situation should not discourage us from making hypotheses and testing them based on what is currently known. This is how we advance scientific knowledge.

My analysis of the issues involved in understanding medicinal fungi will be presented---in addition to this Introduction---in the following sections:

  1. Successful Uses of Micro-fungi: Antibiotics; and Pharmacological Properties of Macro-fungi
  2. Ling zhi, Elixirs of Immortality and Ganoderma sp.
  3. Summary


  1. David Walde, MD; Denis Benjamin, MD; Nicholas P. Money, PhD
  2. Anthea Levi, “Is mushroom coffee the next superfood trend”, Health, January 19, 2017.
  4. See F.D.A. U.S. Food and Drug Administration guide on labeling: Chapter IV. Claims,
  5. John Gever, “Hidden Dangers of Herbal Meds Reviewed”,; “Herbal medicines – toxic side effects and drug interactions” February 12, 2014,
  6. “18 Herbal Supplements with Risky Drug Reactions” July 27, 2017,
  7. Barry McCleary, et al, Measurement of β-Glucan in Mushrooms and Mycelial Products, Journal of Analytical Science International, Volume 99, No. 2, March-April 2016, pp.364-373.
  8. Robert Rogers, The Fungal Pharmacy: The Complete Guide to Medicinal Mushrooms & Lichens of North America, 2011.
  9. Denis Benjamin: Mushrooms: Poisons and Panaceas and Musings of a Mushroom Hunter: A Natural History of Foraging.
  10. Christopher Hobbs, Medicinal Mushrooms: An Exploration of Tradition, Healing and Culture, Botanica Press, OR, 1986.
  11. Greg Marley’s Mushrooms for Health: Medicinal Secrets of Northeastern Fungi, Down East Books, 2009.
  12. Paul Stamets, Mycelium Running: How Mushrooms Can Save the World, Ten Speed Press, 2005.
  13. Rebecca Trager, “Fungi eat up old batteries and spit out metals”, Chemistry World, August 23, 2016.
  14. Julianne Wyrick, “Crowdsourcing unearths promising anticancer compound”, Chemistry World, December 6, 2013.