Fruiting body or mycelium: why it matters in mushroom supplements
Short answer: The fruiting body is the mushroom you can see and pick, while mycelium is the thread-like network it grows from. Mycelium is often grown on grain and ground together with that grain, so the product often contains grain starch. Dried mycelium from lion's mane and reishi is also an unauthorized novel food in the EU, while the fruiting body is allowed.
Last updated: October 30, 2026 · Written by Florian Fermin
Whether a supplement is made from the fruiting body or mycelium isn't always stated on the packaging. Honestly, I find that strange, because it makes quite a difference what you're consuming.
For lion's mane and reishi, we use only the fruiting body, and we clearly state that. Below, I'll explain why that matters.
What's the difference between a mushroom's fruiting body and mycelium?
The fruiting body is the visible part of a mushroom, with a cap, spines, or a hard bracket. Mycelium is the underground network of fungal threads from which the fruiting body grows. They belong to the same organism, but differ in structure, composition, growing time, and, in the EU, legal status.
Mycelium is the vegetative part of a fungus: a network of thin threads (hyphae) that absorbs nutrients from wood, soil, or a growing medium. A fruiting body is the reproductive structure that produces spores.
For lion's mane (bearded tooth, Hericium erinaceus), it's the white ball with dangling spines. For reishi (lingzhi, Ganoderma lucidum), it's the shiny, hard bracket.
| Feature | Fruiting body | Mycelium on grain |
|---|---|---|
| What is it? | The visible mushroom | Fungal threads, grown on a base of grain or rice |
| What's in the final product? | Mushroom only | Mycelium plus the grain it grew on |
| Starch | Low | Often high, due to the grain |
| Growing time | Longer | Shorter and cheaper |
| EU status | Allowed in supplements for most well-known species | In 2019, the EU assessed dried mycelium powder from all these species as novel food (including lion's mane, reishi, shiitake, maitake) |
Why does grain-grown mycelium often contain starch, and why does that matter?
When mycelium grows on grain or rice, the fungal threads grow right through the growing medium. Producers can no longer separate the two, so they are dried and ground together. Some of the final product is then grain starch, and that proportion is rarely stated.
Starch is an alpha-glucan and is counted when you measure only "polysaccharides." So a measured beta-glucan content tells you more. Read all about alpha- and beta-glucans in our article on beta-glucans in mushrooms.
Read how to read a CoA to find out where to find that concentration on a lab report.
Does the composition of fruiting bodies and mycelium really differ?
Yes, fruiting bodies and mycelium have different chemical profiles. In lion's mane, hericenones are found mainly in the fruiting body and erinacines mainly in the mycelium. In reishi, the concentration of triterpenes varies by part of the mushroom and growth stage.
Hericenones and erinacines are two groups of compounds described specifically in lion's mane and studied mainly in the lab (Friedman, 2015). Triterpenes are the bitter compounds in reishi, and according to Wachtel-Galor and colleagues, their concentration depends on the part and growth stage (Wachtel-Galor et al., 2011).
The concentrations also vary widely among retail products. So the name on the packaging tells you little about what is inside. Learn more about reishi in our reishi guide.
Is dried mycelium from lion's mane or reishi actually permitted in the EU?
No, dried mycelium powder from lion's mane and reishi is a novel food in the EU without authorization, so it may not be sold as a food or supplement. The fruiting bodies of both may be used in food supplements. This follows from EU consultations in 2019, which also classified mycelium powder from shiitake, maitake, and oyster mushrooms as novel food.
Novel food means something was not eaten on a meaningful scale in the EU before May 15, 1997, and therefore needs authorization first. For mushrooms, the part used can make a difference. You can find the rulings for each species and part on the European Commission's consultation page.
Cordyceps is different; the species mainly determines what’s permitted. Read more in our article about cordyceps and EU regulations.
How can you tell from the label whether a mushroom supplement is made from the fruiting body or mycelium?
A good label simply names the part used: “fruiting body” for the mushroom itself, “mycelium” or “myceliated grain” for fungal filaments grown on grain. If it only lists the mushroom’s name, you don’t know which part it contains. A measured beta-glucan content is another useful indicator.
- “Fruiting body” or “fruiting body”: the mushroom’s fruiting body was used.
- “Mycelium,” “myceliated grain,” or “mycelium on organic oats/rice”: the product contains mycelium grown with grain.
- Just “lion's mane” or “reishi”: check with the seller.
- Beta-glucans listed: a measured beta-glucan content tells you more than just “polysaccharides.”
I would always look at the fruiting body first. For more ways to compare products, see choosing the best mushroom supplement.
Is mycelium always worse than the fruiting body?
No, mycelium isn’t necessarily worse. The problem is mainly mycelium that’s ground together with its grain substrate, and species for which dried mycelium isn’t permitted in the EU. Mycelium grown in liquid culture and processed separately from its growing medium is actually a different product.
Some studies specifically used mycelium. In a pilot study, 20 healthy adults aged 50 to 75 took 333 mg of Cs-4, a cordyceps mycelium extract, or a placebo three times a day for 12 weeks (Chen et al., 2010). Erinacines from lion's mane are also found mainly in the mycelium (Friedman, 2015).
What hasn’t changed: in the EU, only the fruiting body is permitted for lion's mane and reishi. So for these two, it’s mainly a legal matter.
What part are our lion's mane and reishi made from?
The lion's mane and reishi from GOYU are made from the fruiting body, which is also stated explicitly in the ingredients list. The lion's mane powder label says "Lion's Mane Powder (Hericium erinaceus) (fruiting body)," and the reishi powder label says "Organic Reishi powder (Ganoderma lucidum) (Fruiting body)." The reishi extract also lists "(fruiting body)" after the species name.
| Product | Part | On the label |
|---|---|---|
| Lion's mane extract capsules | Fruiting body | 400 mg 20:1 extract (water and ethanol), 20% beta-glucans, 30% polysaccharides |
| Reishi extract | Fruiting body | 400 mg 20:1 extract, 30% beta-glucans, 40% polysaccharides |
| Lion's mane and reishi powder and capsules | Fruiting body | Ground mushroom, organic (NL-BIO-01), beta-glucan content not stated |
Want to see it in black and white? Send the batch number from your packaging to support@getgoyu.com and you'll receive the certificate of analysis (CoA) for that batch. All forms are listed on the lion's mane page and in the mushroom collection.
Summary in 3 points
- The fruiting body is the visible mushroom. Mycelium grown on grain is ground together with the grain and therefore often contains starch.
- Dried mycelium from lion's mane and reishi is an unauthorised novel food in the EU. The fruiting body is permitted.
- Check the label for the part used and a measured beta-glucan content, not just "polysaccharides."
Frequently asked questions
Is mycelium inferior to the fruiting body?
Not necessarily, but mycelium grown on grain often contains starch and has a different composition. In the EU, dried mycelium from lion's mane and reishi is also not permitted.
Why do brands use mycelium?
Mycelium grows faster and is cheaper to cultivate than a fully grown fruiting body.
What's the difference between alpha- and beta-glucans?
Alpha-glucans include starch. Beta-glucans are found in the cell walls of mushrooms. Only the beta-glucan content indicates the proportion of mushroom polysaccharides.
What does "myceliated grain" mean on a label?
Grain that has been colonized by mycelium and then ground whole. So the product contains both fungal filaments and grain.
How do I know which part is in my supplement if it isn't listed on the label?
Check with the supplier, preferably together with a batch analysis certificate.
Sources
- Friedman M. Review article on the chemistry and nutritional value of Hericium erinaceus (fruiting body and mycelium). J Agric Food Chem. 2015;63(32):7108-7123. Europe PMC 26244378
- Wachtel-Galor S, Yuen J, Buswell JA, Benzie IFF. Ganoderma lucidum (Lingzhi or Reishi). In: Benzie IFF, Wachtel-Galor S, editors. 2nd ed. Boca Raton (FL): CRC Press/Taylor & Francis; 2011. Chapter 9. NCBI Bookshelf NBK92757
- Chen S, Li Z, Krochmal R, Abrazado M, Kim W, Cooper CB. Effect of Cs-4 (Cordyceps sinensis) on exercise performance in healthy older subjects: a double-blind, placebo-controlled trial. J Altern Complement Med. 2010;16(5):585-590. Europe PMC 20804368
- European Commission. Consultation on novel food status: Hericium erinaceus dehydrated mycelium powder, conclusion: novel food, October 29, 2019. food.ec.europa.eu
- European Commission. Consultation on novel food status: Ganoderma lucidum dehydrated mycelium powder, conclusion: novel food, October 29, 2019. food.ec.europa.eu
- European Commission. Consultation process on novel food status (overview of all decisions, including shiitake, maitake, and oyster mushroom mycelium powder, October 29, 2019). food.ec.europa.eu, accessed October 22, 2026.
- Packaging texts for Lion's Mane Powder, Reishi Powder, and Reishi Extract Capsules (ingredient list), accessed October 15, 2026.
This article is for informational purposes and is not medical advice. Food supplements are not a substitute for a varied and balanced diet and a healthy lifestyle. If in doubt, or if you are pregnant or taking medication, consult your doctor or pharmacist.
Mushrooms from GOYU
Lion's Mane, reishi, chaga, cordyceps, and shiitake as powder and capsules (without fillers), most also as extract capsules (20:1).
