Myceliated Grain Vs Filler

Myceliated Grain vs Filler

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Host Defense has proudly focused on mushroom mycelium since the 1990s when founder and Chief Science Officer, Paul Stamets, created a dietary supplement line. Based on years of research, Host Defense products use a mycelium biomass foundation which contains a unique matrix of mushroom mycelium with enzymatically-converted organic brown rice substrate, 'cultured' together - with no fillers! This unique matrix of mycelium and fermented substrate - also known as ‘mycelium biomass', ‘myceliated rice’, or ‘myceliated grain’ - work together to support a variety of body systems for overall wellness.* 

What is ‘Myceliated Grain’?

‘Myceliated grain’ is the unique ingredient formed when mushroom mycelium consumes and converts a grain substrate through a fermentation process not unlike tempeh, yogurt, or kombucha. The combination of mycelium and fermented substrate is commonly referred to as ‘myceliated grain’ or ‘mycelium biomass’.

What is ‘Myceliated Grain’? Finger pointing to mycelium grown on brown rice

There are a number of fruit body-only supplement brands that have launched entire marketing campaigns designed to downplay the benefits of mycelium and the fermented substrate as a way to lend credibility to their own products. They refer to mycelium and the fermented substrate as ‘myceliated grain’ and show pictures of mushroom fruit bodies alongside images of mycelium growing on rice or oats as a way to indicate that their products are “more natural” or “of higher quality”. They say that the mushroom fruit body is superior to mycelium, and therefore also superior to a mycelium product that includes the substrate it’s grown on. Some of these same brands also claim that mycelium products are of less overall value and benefit to the consumer.

Because the mushroom fruit body is the more widely-recognizable stage of the fungal life cycle, and what typically comes to mind when thinking about ‘mushrooms’, it’s easy for many people to accept this line of messaging if they aren’t aware of what the science demonstrates. However, identifying the fermented rice as ‘filler’ and mushroom mycelium as “less beneficial than the fruit body” ignores a vast body of research and data that continues to accumulate in scientific literature. At Host Defense, we take an informed approach to our product formulation by acknowledging the enormous potential of the entire fungal organism and that’s why we use myceliated grain - or mycelium biomass - as the foundation of all our product formulation.*

What is ‘Mycelium Biomass’?

‘Mycelium biomass’ is another name for ‘myceliated grain’, which is the combination of mushroom mycelium and its fermented substrate. We use an organic brown rice substrate to grow our mycelium, and the converted, fermented brown rice becomes a completely new, uniquely active ingredient that supports and complements the health supporting benefits of the mycelium.* 

Mycelium and Fermented Substrate vs Filler

There's a lot of misinformation about the use of mycelium because it requires a food source - or the substrate - to grow for use in consumer products. Common claims that mushroom fruit bodies not only offer more value to the consumer, but that mycelium products that include the substrate, have fewer health-supporting benefits and are nothing but a mixture of mycelium and ‘filler’. However, there is a fundamental difference between a SUBSTRATE and a FILLER. The mycelium and fermented substrate - also known as ‘mycelium biomass’ or ‘myceliated grain’ - is a unique ingredient that has been converted as mushroom mycelium consumes and ferments a food source, whereas a ‘filler’ is an inactive ingredient that serves to add weight or bulk to the main ingredient. But the substrate, once fermented, is actually immunologically active and complements the health-supporting benefits of the mycelium.* 

What is a Mycelium Substrate?

A mycelium substrate is used in a controlled setting to grow mushroom mycelium for the use of supplements and other mycelium-based products that consumers can use to support various body systems. That means the substrate must be both a nutritious food source for the mycelium and also be beneficial to humans. Unlike growing fruit bodies, which are separated from their food source when harvested, the mycelium substrate becomes transformed by the mycelium, creating a nearly inextricable matrix. We believe the unique combination of both the mycelium and its substrate are one of the reasons our mushroom mycelium products are so effective.* 

What is a mycelium substrate? Lion's Mane Mycelium in a petri dish.
We grow our mycelium to this phase in the mushroom life cycle: the critical nexus whereupon the mycelium gives birth to primordia, the earliest stages of mushroom formation. This nascent stage is when the mycelium is most empowered! Truly stellar!

The process to grow mushroom mycelium in a controlled setting is not unlike that of several other well-known functional foods, like tempeh, yogurt, and kombucha. For each of those highly beneficial foods, a growth medium - called a “substrate” - is introduced as a food source for the bacterial and/or fungal organisms:* 

  • Tempeh is made through a natural culturing and fermentation process in which a fungal organism binds to and ferments soybeans until tempeh is formed. 
  • Yogurt is formed when probiotic bacteria are introduced to milk and allowed to ferment.
  • Kombucha is formed when a mix of sugar and tea are fermented using a culture of bacteria and yeast (a fungal organism). 

In each of these instances, the substrate is fundamentally transformed as the primary ingredient digests and metabolizes it. The process of fermentation makes the end result appear very different from the original individual ingredients. And in addition to the original nutritional profile, the newly-fermented final result also offers the added health-supporting benefits that result from the fermentation process itself. At Host Defense, all of our products use both the mushroom mycelium and the fermented substrate - because it works!*

What is a Filler?

A ‘filler’ is nothing more than an additive. It is an ingredient that either serves to add bulk or weight to the end product, but a filler has no discernible health benefit. Fillers are added to everything from supplements and seasoning salts, to processed meats and fast foods. They are often intended as an inexpensive bulking agent that makes the final product more cost-effective for the manufacturer.

Fermented Substrate vs Filler Chart for Mushroom Supplements

There are no ‘fillers’ used in any Host Defense products. Rather, both the mushroom mycelium and the fermented rice substrate used in all of our products - including capsules, powders, extracts, and more- have been researched, tested, and may offer health-supporting benefits.* 

Our Organic Brown Rice Substrate

Mycelium requires a food source to grow. When cultivated for use in human supplements, mycelium can be grown on a substance like rice or oats, which is safe for consumption by both the mycelium and humans. At Host Defense, we use an organic brown rice as our substrate because it is generally well-tolerated by most people, and it serves as a nutritious food source for the mycelium. Once consumed and fermented by the mycelium, the rice is transformed into an entirely new substance - just like with tempeh, yogurt, and kombucha. Under normal conditions, the matrix of mycelium and the fermented substrate are inseparable. However, in a laboratory setting it is possible to extract the two and test each one individually. When separated out, research suggests that once the rice has been fermented, it becomes an entirely new and immunologically active substance that complements the health-supporting properties of the mycelium.* 

Organic brown rice substrate in a glass bowl

Host Defense® mushroom mycelium is grown on an organic brown rice substrate that becomes fundamentally converted as the mycelium consumes, cultures, and transforms the rice into a fermented, myceliated, nearly inextricable matrix. As with the examples of tempeh, yogurt, and kombucha, the process of fermentation completely transforms the substrate, and the resulting myceliated rice - or mycelium biomass - is immunologically active.*

Benefits of Myceliated Brown Rice and Mycelium*

There are hundreds of articles published in the scientific literature demonstrating the health-enhancing value of mushroom mycelium grown on grain substrates such as organic brown rice, including a 2019 NIH funded study confirming the immunologically supportive activity of Host Defense® Turkey Tail mycelium-based capsules.* Research confirms that the beneficial mushroom mycelium and the fermented substrate both offer health-supporting benefits.*

Myceliated Brown Rice and Mycelium. Progression from mycelium and organic brown rice to mycelium and the fermented substrate

Research Conclusions

Independently collected data shows that in Host Defense® products, the myceliated rice is transformed into an immunologically active superfood that complements the health-supporting compounds of the mycelium.* 

At Fungi Perfecti, we stand by the scientifically proven results of our products. This is why our formulations include mushroom mycelium as the foundation for all of the products in the Host Defense® Mushrooms™ line - including capsules, powder, extracts, and more!*

We Grow Our Own

Another important differentiator of Host Defense products is that we grow our own mushroom mycelium and fruit bodies. We don’t purchase from a third-party. We especially don’t use imported mushroom fruit bodies or mycelium. Mushrooms are bioaccumulators, meaning that they accumulate - or absorb - both nutrients and toxins from their environment. It’s one of the things that makes it possible for them to support the health of the surrounding ecosystems in their native environments. They pull toxins, pollutants, and harmful substances out of their immediate surroundings, keeping the native habitat from harm. However, those toxins live on in the fruit bodies that absorb them, and when wild-harvested for use in mushroom supplements, it can be nearly impossible to ensure a clean product for consumption. 

Farm Gate- We Grow Our Own Mushrooms and Mushroom Mycelium

Our Grow Practices

In order to confirm the safety and quality of our supplements, we grow all of our own mushroom mycelium and fruit bodies. We start by collecting samples from mushroom fruit bodies in the wild. This method requires only a small sample, leaving the wild mushroom fruit body and its surrounding native ecosystem intact and unharmed. We bring these samples back to our culture library, where we use proprietary culturing techniques to filter out any possible pollutants while preserving genomic integrity. Then, on our certified organic farm in Washington State, we grow our own mushroom mycelium and fruit bodies, using an organic brown rice substrate for our mycelium and alder wood chips for our fruit bodies.

Organic Mushroom Farm, No Spray

In addition to ensuring that our mushroom mycelium and fruit bodies are sustainably grown and free from contaminants, our production practices also guarantee that our supplements contain absolutely no fillers. Because we keep our mushroom mycelium and fruit body cultivation in-house we know there’s nothing there that we haven’t chosen to include - from the forest, to our farm, to you.

Commitment to Transparency & Research

Fungi Perfecti Research and Development Team

Transparency is important to us. As part of our foundational value system, we continue to invest resources into furthering our understanding of mushroom mycelium and fruit bodies to share with both our consumers and the mycological community at large. We employ a full-time team of dedicated scientists that include mycologists, botanists, biologists, chemists, and medical professionals, including 5 PhDs and 5 full time researchers on our Research & Development Team. These highly trained scientists are committed not only to testing the safety, quality, and benefits of Host Defense® products, but also to looking for new and innovative ways to utilize the immune-supporting benefits of the mushroom organism, at each of the various stages of the life cycle that the fungal organism moves through. Mushrooms are fascinating, complex, and highly nuanced. We believe we are only at the beginning of learning what they have to teach us, and we will continue to evolve as we learn more about what they have to offer. Harnessing the power of mushroom mycelium in the form of human supplements is one way we have chosen to evolve as science demonstrates the enormous benefits available to us.*

At Host Defense® we follow the science. And years of industry-based research, along with both internal and third-party testing, demonstrates that our mycelium-based mushroom products offer significant immunological support.* 

Paul Stamets and Renee Davis, MA in the lab looking at petri dishes


"In my scientific opinion, mushroom products not incorporating mycelium are at a decided disadvantage, given the results of recent research."* 

 Paul Stamets


*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.

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