We know that spending time in forests is great for mood and muscles as well as a fun way to train immune cells for better performance. For more on how forests grow better immunity, check out this blog post on the topic. Now just imagine what it’s like to be a mushroom growing on the forest floor or in a fallen tree. When you eat an edible (and appropriately-identified) wild fungus you’ve expertly wildcrafted on your own, its flavor tells you—and your immune system—all the latest news and weather that helped design the earthy tastes and textures that are so unique to each edible mushroom.
No Other Food is Quite Like Mushrooms
Mushrooms are a distinctive form of life—fleshy, nourishing fungi that thrive in damp, shaded, hidden places. Some are tasty comfort foods, while others are mainly medicinal, containing proteins, peptides (think of these as protein fragments that can sometimes alter body function), indigestible polysaccharide sugars, and unusual antioxidants.
These mushroom components tend to have complex shapes and chemical makeups that are fascinating and information-dense to the human immune system. Immune cells along the digestive tract study these compounds intensely as mushrooms are being digested, and when immune cells circulating in your bloodstream interact with them, they can change the way your system reacts to microbes, allergenic substances, or even toxic chemicals.
Why Are Some Mushrooms Considered Medicinal?
Medicinal mushrooms have diverse health and immune specialties, so let’s take a look at a few:
- Shiitake mushrooms (Lentinus and Lentinula species) contain polysaccharides called beta-glucans, and the main beta-glucan is called lentinan. Lentinan has been studied extensively for its effects in certain cancers, where it sometimes helps poorly-regulated cancer cells complete their life-and-death cycles. Shiitake also contains other plant nutrients that improve the immune response to microbes.
- Lion’s Mane (Hericium species) is perhaps best known for its unique antioxidants (called erinacines and hericenones) that seem to zero in on nerves and brain structures, helping them create new connections while protecting them from excessive immune activity.
- Cordyceps (Cordyceps, Ophiocordyceps, and Paecilomyces species) is quite extraordinary—it completely digests certain insects, transforming their resources into a distinctive mushroom with potent peptides and polysaccharides. Cordyceps may help strengthen certain aspects of immune defense, and a few studies indicate it may also help to protect lung, muscle, and kidney function.
- Reishi (Ganoderma species) contains a complex blend of proteins, antioxidants, and polysaccharides, and is often used as extracts that are prepared in ways that maximize these ingredients’ potencies. Reishi and its components may help the body create more of glutathione, a human-made antioxidant that is favored by the heart, brain, and other vital organs. Supplementation with reishi has shown positive effects on people who are chronically stressed out and have high levels of the stress hormone cortisol.
- Turkey Tail (Coriolus and Trametes species) is especially famous for its specialty polysaccharides, called PSK and PSP. PSK readies the immune system for a better defense against potential microbial invaders. PSP, on the other hand, seems to work by improving the gut flora, which is crucial for immune function that is effective yet doesn’t go overboard. This is a great combination of effects that keep immunity precisely focused on the right targets!
- Oyster mushrooms (Pleurotus species) are one of the best sources of the antioxidant ergothioneine, which is known to protect DNA—our genetic source code—from damage. They also naturally contain GABA (yes, gamma-aminobutyric acid, just like the brain messaging chemical!) and lovastatin (yes, just like the statin pharmaceutical!). Oyster mushrooms also furnish a beta-glucan called pleuran, which appears to aid immune function most specifically in the lungs.
Sounds like a lot of complicated words? Let’s bring it back down to earth, since that’s where it all started! Mushrooms are simply, by the very nature of their existence, extremely immune-active foods. They also happen to be quite low in calories, because it’s a lean living on the forest floor! Yet they contain massive amounts of environmental data that your immune system can use for updating and improving its function.
Mushrooms are Microbiome Food!
One last, huge detail about mushrooms is that all those polysaccharides and beta-glucans are fantastic food for the friendly microbes that make their home in our intestines—our gut microbiome. For more about the inner life of your gut bacteria, check out this previous posting on the topic. This microbial community is able to transform these fiber-like substances into health, life, and energy, and they pay us back the favor by helping keep our critical intestinal defenses up to date.
For a deeper dive into how mushrooms nourish the ‘gut bugs’ that train human immunity, here’s a recent scientific article on the subject.