maitake mushroom in forest

Best Quality Mushroom Supplements - Mycelium vs. Fruiting Bodies

Mushroom supplements are finally becoming popular for their vast array of health benefits. But not all mushroom supplements are created equally. To understand what makes a high quality mushroom supplement, we should first look at a mushroom’s life cycle.


mushroom life cycle

                                              Mushroom life cycle 


The actual mushroom itself is called the fruit (or fruiting) body. It produces spores, the spores germinate and create a network of mycelium (almost like roots). The mycelium eventually produces a pinhead (or primordium), which grows into a new whole mushroom, and the cycle of life continues.

                                           Reishi fruiting body


How can we relate this to the nutritional merit of mushroom supplements? It should be obvious that for the most nutritional value we want the whole mushroom. After all, it is the fruit. It is the organism’s final form. It contains the sum of all of the healthy compounds like beta glucans which the organism worked so hard to produce.

The mycelium are like the roots of the mushroom. They are very light, thin, wispy, almost like spider webs. While they may contain trace amounts of the beneficial compounds like beta-glucans, their mass is too slight to contain any significant nutritional value. Their purpose is to channel their collective resources into producing an actual mushroom. The fruiting body is the final culmination of these resources, and that’s why it actually is a significant source of nutrition and active compounds.


Myceliated Grain (Grain Spawn)

Mycelium are typically implanted on sterilized rice or grain in a lab. The grain has mostly been colonized and now could be called grain spawn. However, if this jar pictured were were shaken up, the mycelium would mostly fall away and reveal that the vast majority of the mass of the grain spawn is in fact just grain. Shockingly, many supplement companies grind this grain spawn into a powder and sell it as a medicinal mushroom supplement. These products often taste slightly starchy or salty, like a very plain bran cereal. They do not taste like mushrooms because they’re devoid of both the fruiting bodies and their active compounds.

These supplements are often marketed as “full spectrum”, but this is empty marketing jargon and these products will always be a very high percentage of grain by weight. Except for tincturing and liquid extracts, there is no way to separate the ultra thin, wispy, low density mycelium from the substrate (the grain) it's growing on. Most medicinal mushroom studies use whole fruiting bodies.

study published in June, 2017 tested 19 batches of Ganoderma lucidum purchased in the U.S., mostly from Amazon and Ebay. They used a very comprehensive toolkit of scientific testing methods to determine the quality consistency of the samples. Of the 19 samples, only 5 (26.3%) tested in accordance with their labels. “In accordance with their labels” basically means that they were identifiably Reishi. The main way to identify the sample as actually being Reishi is to test for the active compounds. 1,3-β-D-glucan, arguably the most important for health benefits and certainly the most touted compound in G. lucidum, was only detected in 5 out 19 tested products. Many of these products were likely mycelium based. This study concluded that, overall, the quality consistency of U.S. Reishi supplements is extremely poor.


This is usually how the supplement facts panel of a mycelium-based product will appear. They should disclose the fact that it is mycelium and not whole fruiting bodies. However, other companies are more deceptive and simply list the names of the mushroom species without clarifying whether they are fruiting bodies or mycelium. It is important to be a discerning consumer and do your research. If the company isn’t clearly stating that their product is made from whole fruiting bodies, and what percentage is such, they are likely composed of mostly grain dust.


Things to look for in a medicinal mushroom supplement:

  • Make sure the product is stated to be 100% fruit bodies. If it’s stated that it’s “full spectrum”,  or some combination of mycelium and fruiting bodies, then it’s impossible to know the ratio. The product could be 99% grain and 1% mushrooms. Make sure the product is clear and specific about its ingredients.
  • Check the color of the product. Mushrooms blends (depending on which species they contain) should be a rich, dark color. Reishi and Chaga specifically are dark in color. A very lightly colored or tan product may be a sign that it’s grain based.
  • Smell and taste the product. If it smells like starchy, salty, or like cereal, oats, grains, etc., then it likely does not contain much actual mushrooms. Real mushroom powders can smell earthy, musty, fishy, malty, or even chocolatey, depending on the species or the blend. They should have a rich smell and will not smell starchy or like cereal.


There continues to be a lot of conflicting information about the quality of mushroom supplements on the market. Some companies claim that mycelium-on-grain powder is the best. But it's indisputable that mycelium powder comes a high percentage of substrate (oat or grain) because the mycelium is inseparable from the substrate. It's also indisputable that real mushroom fruit bodies are rich in beta-glucans and health-promoting compounds.


1. Wu, D., Deng, Y., Chen, L. et al. Evaluation on quality consistency of Ganoderma lucidum dietary supplements collected in the United States. Sci Rep 7, 7792 (2017).

Back to blog