Christopher Hobbs, phd, lac, ahg, will present on the clinical use of mushrooms and herbs to treat infection at the 14th Annual International Conference of the Association for the Advancement of Restorative Medicine, September 15 to 18, 2016, in Hilton Head, South Carolina. He is a fourth-generation, internationally renowned herbalist, licensed acupuncturist, herbal clinician, research scientist, consultant to the dietary supplement industry, expert witness, botanist, and mycologist with more than 35 years of experience.
The author or coauthor of more than 20 books, Christopher lectures on herbal medicine worldwide. He has taught at universities and medical schools such as Stanford Medical School; University of California, Santa Cruz; Bastyr University and the National School of Naturopathic Medicine; and most recently for 7 years at the University of California, Berkeley, as a graduate student instructor and lecturer. He earned his PhD at UC Berkeley, with research and publication in evolutionary biology, biogeography, phylogenetics, plant chemistry, and ethnobotany.
For more information about the conference, visit http://www.restorativemedicine.org/.
Integrative Medicine a Clinician’s Journal (IMCJ): Mushrooms are often considered to be filler when it comes to nutritional profiles. Could you talk a little bit about the nutritional profile of mushrooms and how they can contribute to functional diets?
Dr Hobbs: When most people think of mushrooms and nutrition, they think of button mushrooms from the store, Agaricus bisporus. They are often used just as a little flavorful dressing or garnish on a salad, though I think that’s changed quite a bit over the last number of years. People are starting to eat more shiitake mushrooms, which have been cultivated for a long time, maybe 800 years. The number-1 cultivated mushroom in the world is Agaricus bisporus, the button mushroom, but second is shiitake. If you go to into a Chinese restaurant, the Chinese black mushrooms that you get are shiitake. However, they do not really taste like fresh shiitake that have been cooked. The ones that you generally find in Chinese restaurants have been dried and might have been around for a while, and then they are reconstituted and cooked in different dishes.
Mushrooms are really out there and are widely available. They are served everywhere now, but they do not really get the credit they deserve for being such a nutritional powerhouse. Oyster mushrooms are also quite popular and can be found in a lot of markets. They come in different colors: pink and yellow, even blue, and then white or off-white, like you would find in the woods. They grow all over the world. Oyster mushrooms are the most digestible of all mushrooms. Some species of oyster mushrooms contain up to around 30% useful protein, and by that I mean the protein is very absorbable and has the full complement of amino acids that we need. Shiitake mushrooms are not quite as digestible as oyster mushrooms, but they still contain quite a bit of protein, up to about 25% of usable protein. Besides the protein, there are a lot of trace minerals in mushrooms. Mushrooms are also a great source of phosphorus, potassium, zinc, copper, magnesium, and other minerals.
Besides minerals, mushrooms contain a lot of B vitamins. By the way, many mushrooms, including shiitake, especially after being exposed to the sun, contain quite a bit of vitamin D. It is in the form of ergosterol in mushrooms, and when they are exposed to the sun, they actually transform that compound into vitamin D2—ergocalciferol—that can be used by people. Mushrooms are also a very good source of digestible and indigestible fiber—we all need more fiber; there is no doubt about that.
They are also low calorie. Mushrooms are not sweet, so they are an ideal diet food, with a high nutritional profile, lots of protein, high fiber, and low fat. I think when people really take a second look at what mushrooms can offer in the diet on a regular basis, people will start eating more mushrooms.
It is really fun to go out in the woods and hunt wild mushrooms as well, like porcini and oyster mushrooms. Of course, you have to be really careful about what you are picking, because there are some lethal mushrooms out there like the death cap. Go on mushroom walks and make sure you get a good guide or two. Hunting wild mushrooms can provide a lot of health benefits, besides the nutritional benefits, for instance walking in the forest, getting the fresh air, moving your body—all very uplifting and healthful.
IMCJ: When it comes to vegan and vegetarian diets, sourcing B12 is a concern. Are there particular varieties of mushrooms that have higher B12?
Dr Hobbs: Again, oyster mushrooms. The form of B12 in mushrooms is not as usable as the vitamin sourced from meat, but it is still somewhat useful. I would say 25% of what is found in mushrooms can be utilized by the body. It is a good source if you are eating mushrooms regularly, especially for vegetarians. As far as which other ones contain the most B vitamins, I think shiitake has a pretty good complement, as well as oyster mushrooms. Porcini also has some B vitamins—not quite as usable but still a good source.
IMCJ: Is cooking necessary to unlock some of the nutrients, or are we able to access them from the raw state?
Dr Hobbs: As a good general rule, always cook mushrooms. There are some exceptions. I eat a few things out in the woods, like witch’s butter, which is pretty tender. I eat that in the raw form, but not excessive amounts of it. Most mushrooms should be cooked. The reason why is because they contain a tremendous amount of fiber that is mostly indigestible by us, including chitin, which is an amino polymer, and lots of heteropolysaccharides, which are bound up with chitin and also other polymers in the cell wall. Heating it, steaming it, or cooking it even lightly can break down some of those insoluble fibers and allow better access to the nutritional aspects—the minerals and the vitamins—along with the beta glucans, which are essential to the immunomodulating activity of fungi.
One paper that was published recently—and this is really quite an interesting study by a group who—did an ex vivo study where they fed people mushrooms, drew blood, and then challenged the blood that had leukocytes and other immune cells in it with a virus or bacteria. They found that, when the mushrooms were cooked and not just dried or eaten raw, the immune system had more activity against pathogens. It is clear from the literature that it is very important to cook mushrooms for the strongest immunomodulatory activity, and also to get more nutrients out of them.
If you eat raw or undercooked mushrooms, even shiitake, they can be quite nauseating to some people. I have experienced that a number of times eating meals with mushrooms when they were not cooked properly, especially if you’re eating more than one species at a time. You can get pretty green after eating a plate of mushrooms if they are not well cooked.
IMCJ: How would a clinician go about using mushrooms for immune support?
Dr Hobbs: There is a lot to it, that’s for sure. There are so many species being used today. We ask: Is one species any better than another? What are the most popular ones? How much is the proper dose? Also, there are commercial products, leading to questions and interesting discussions about what the best commercial products are. Is the mycelium better, or the fruiting body? Because products are made from the fruiting body or the mycelium. I think, first of all, if a practitioner is going to be interested in using mushrooms for immunomodulation, supporting immune function, and preventing different illnesses, or even as an adjunct part of a treatment program, then first you have to know what the best products are, how to use them, what the proper dose is, and so forth. That is a really important discussion that is going on in the dietary supplement industry, and among practitioners. I have found misunderstandings about these questions.
I think we can all realize that mushrooms have come on the scene as a therapeutic option these days. I just had a conversation with a major mushroom supplier who said that some major food companies now are starting to get interested in the immunomodulatory effect of mushrooms—how they can add that into their food product lines. I am talking about major food manufacturers. It really is starting to get into the mainstream, now.
As far as use in the clinical setting, again, the practitioner has to make sure to use enough. Research clearly shows that there is a threshold you have to reach before they become active. Too little is not going to be active, and with too much—if you’re giving too high a concentration—that also could be problematic. Some research shows too much of these immunomodulatory compounds in your body could have a mildly suppressive effect. There is a sweet spot where you want to achieve the proper dose, not too much or too little.
As far as the form goes, I just finished an article for HerbalGram that is going to be coming out in the next issue and discusses commercial medicinal mushroom products. So stay tuned for that. There are a lot of factors. The main active compounds in mushrooms are polymers, beta glucans, which are part of the cell wall. We actually have ancient receptor sites for them in our gut. Believe it or not, 60% of our immune tissue is in our gut. When we ingest mushrooms, these compounds—these higher molecular weight compounds, again beta glucans—are complexed with proteins, chitin, and other molecules. Our bodies can recognize those. We have specific binding sites that can actually recognize these compounds and say, “Hey, there’s some fungi in our body and that could be a problem, and so, mount an immune response.” That is one of the main mechanisms by which they work. It is a very ancient pathway of recognition.
IMCJ: When it comes to mushrooms’ effects on cancer, are there multiple mechanisms in play based on the type of cancer and the type of mushroom, or do they all work in a similar way?
Dr Hobbs: In each mushroom species, the branching pattern of the beta glucans is different. For instance, they might be different sizes. They are also in different tertiary forms as well. Each mushroom species really is unique.
The big questions would be: Which mushroom is the most potent, and which one provides the greatest benefits? Of course, according to traditional medicine, some varieties have been utilized for a long time, such as reishi and shiitake, and of course, turkey tails. Each one is quite different. I was mentioning the tertiary structure. The beta glucans in the mushroom cell wall form a helix, so they are coils. Research shows that if they are in the coiled form rather than the straight form, or if they are in pieces because of too much heating, then they are less effective. They are less stimulatory.
Does the species affect it differently? Does it stimulate different vector cells like macrophages, or other leukocytes? Yes, that is the case, so I think if you really look deeply into the literature, you can see that turkey tails may be a stronger stimulant of certain different cytokines, whereas reishi might have other effects. However, all mushrooms have beta glucans, and all mushrooms have immunomodulatory activity, and that includes button mushrooms, porcini, and maitake. Even these edibles have the same type of immunestimulatory compounds in them as the major medicinal species like reishi and shiitake. The types of polymers in the major medicinal species may have especially potent effects versus edible mushrooms that haven’t particularly been noted for their medicinal effects, but that has not been adequately studied.
There is an extensive literature if you want to really dig deeply, and you can see that each species has certain effects that have been noted. Some cytokines are more stimulated than others. Yes, it is quite complicated. At this point, we need more human studies. There are quite a few human studies that have been performed, but only on a few species. We need more, and some of the existing studies are not up to modern standards. Probably 50 species have been extensively studied for their immunomodulatory effects.
IMCJ: Clinically, how do mushrooms work for providing adjunctive cancer therapy?
Dr Hobbs: Turkey tails, Trametes versicolor, which is the most widely researched mushroom, certainly has the most clinical trials of any of the mushroom species, especially considering oral application only, not IV administration. The best of the clinical trials, and the best results that they have achieved, show one group of people using chemotherapy by itself and the other, chemotherapy plus turkey-tail extract. The 5-year survival rate in the group of people taking the mushroom plus the chemotherapy was reported to be up to one-third higher than the group that was not taking any of the mushroom products, only chemotherapy. That is pretty significant. Not only that, but it was shown that, in the mushroom group, nausea was less, energy was better, and just general mood and quality of life were better. As adjuncts to modern, or, I might say modern medical treatments like chemotherapy, mushrooms can offer incredible support for reducing symptoms and improving quality of life.
IMCJ: Do they have any effect on cachexia?
Dr Hobbs: Now that is an interesting question. I do think there are several studies with turkey tails on reducing that rapid weight loss that often occurs, especially as cancer progresses. I do not recall exact papers, but I seem to recall that there was an effect. I do not think it is a huge effect, however. That is very difficult to reverse, obviously, once it begins.
IMCJ: How about mitigating complications, such as infections and pneumonia that plague people who are going through the chemotherapy and radiation?
Dr Hobbs: Chemotherapy and radiation are so immunosuppressive. There is a lot of research that shows the single most-important factor for a good outcome in cancer, in general, is a strong immune status. It is unfortunate that the major treatment, chemotherapy, is very, very strongly immunosuppressive. It hardly makes sense. Fortunately, in adding mushroom medicine extracts like turkey tails to the mix, you can counteract that immunosuppression to a certain extent. That is a key feature of using medicinal mushrooms with conventional treatments. You can counteract immunosuppression, at least to a degree that can still provide a real benefit to the patient.
IMCJ: Is the clinical potential for mushrooms defined at this point, or is that something that is still evolving?
Dr Hobbs: It is rapidly evolving, definitely. We need more clinical trials to really show which species may be better than another, and what format to use. As one example, I do not recommend tinctures of medicinal mushrooms for immunomodulation because that interferes with the activity, and actually the tertiary structure of the glucans. Foremost among the problems with tinctures for immunotherapy is that the fungal beta glucans are not soluble in alcohol!
Mushrooms also have small molecular weight compounds in them, like triterpenes. Those have other effects, for instance, on the nervous system. Reishi is well known for insomnia and other things that may be attributable to the triterpenes. Those are soluble in alcohol, but the fungal beta glucans are very specific to mushrooms, and those are what we are talking about. It has to be a dried, powdered extract, in my opinion.
There are so many products out there on the market that are getting more and more popular, especially in the last few years. Many practitioners are prescribing them. Many people are going into the store and buying them. You see these 4-color boxes in the health-food store showing lion’s mane or showing turkey tails. They are very attractive, and they have labeling and implied claims like immunomodulation, reducing infections, and so forth. So many people are taking them and really without much knowledge about what the effects might be. One thing that I always want to point out in my talks on medicinal mushrooms is: Don’t get your expectations too high. They are not magic bullets. They are not going to—just by themselves—cure cancer or a viral syndrome.
They really are adjunct treatments to support immune function, but they really should go along with all the other things that we know. In other words, an integrated approach, such as diet and exercise and meditation, as well as stretching and mindfulness—all the things that a good practitioner would recommend for a total program for health in viral syndromes and any syndrome or disease involving the immune system.
On the other hand, I do not want to be discouraging, because I think they are incredibly helpful. I prescribed them in my clinical practice and have taken them myself for years and years, and I have seen a real benefit in energy and mood. As you know, if there is immunosuppression, that affects a lot of different processes in the body. Remember that the immune system, the hormonal system, and the nervous system are all integrated.
If you have immunosuppression, that is going to affect the nervous system function, the mood, and hormonal balance. By addressing immunosuppression, or by using immunemodulators such as medicinal mushrooms, you can get a lot of benefit. On the other hand, I do not want people to get the idea that this one medicine is going to resolve all their issues, because it really isn’t. It is used along with all these other things and it can be incredibly helpful, and it should be in everybody’s clinical practice as one valuable medicine in the medicine chest—not by itself, particularly.
IMCJ: What more will people learn by attending your lecture at AARM?
Dr Hobbs: Well, of course, I will address how to choose the best products and what criteria are most important—that is, absolutely key to success with medicinal mushrooms. I will discuss how to actually make mushroom extracts that can be highly effective. This is getting the raw mushrooms, ordering a pound of dried shiitake mushrooms, and making your own right in the kitchen with a blender, a pot, and a dehydrator. I will also discuss what type of fillers are used in commercial products and what type to use if you’re making them at home.
I will also talk about how to choose the best commercial product. Also, proper dose will be discussed, and I will review the clinical trials. I am going to carefully review what clinical data that we have. Then we will talk about the biological effects. How do they work? What are the cellular stimulating mechanisms involved in immunomodulations after ingesting these fungal beta glucans? It is quite a fascinating story.
I will talk about mushroom nutrition. More specifically, I have got some really fascinating charts showing mushroom nutrition, such as what levels of minerals, vitamins, and so forth are in them. It is going to be a carefully considered view of the whole range of medicinal mushrooms.
Footnotes
Facilitated by the Association for the Advancement of Restorative Medicine (AARM) 14th Annual International Conference, to be held in Hilton Head, South Carolina, from September 15 to 18, 2016.