The single biggest quality distinction in the category, and the one most often obscured on a label.
The two parts
The fruiting body is the mushroom — the white cascading thing that gives lion's mane its name. The mycelium is the root-like network it grows from. Both contain actives, but different ones: hericenones concentrate in the fruiting body, erinacines in the mycelium.
The grain problem
Commercially, mycelium is almost always grown on a sterilised grain substrate — usually rice or oats — because it is fast and cheap. At harvest the mycelium cannot be separated from the grain, so the whole block is dried and ground together.
The result is sold as 'mycelial biomass'. A significant proportion of it is grain starch. This is why some labels state 'polysaccharides' rather than 'beta-glucans' — starch is a polysaccharide, so the number looks impressive while measuring mostly rice.
Beta-glucans are the honest measure. Polysaccharides are the flattering one. A label that chooses the flattering one has told you something.
Is mycelium worthless?
No — and it would be dishonest to say so. Erinacines are found in mycelium and are arguably the more interesting compounds, being smaller and more likely to cross the blood-brain barrier. Liquid-fermented mycelium, grown without a grain substrate, is a legitimate and well-studied product.
The problem is not mycelium. It is mycelium-on-grain sold at fruiting-body prices with the substrate uncounted.
How to read a label
- "Fruiting body" stated explicitly — good.
- "Mycelial biomass" or "mycelium on grain" — the grain is in the weight.
- Beta-glucan percentage stated — good. 25%+ is a real extract.
- Only "polysaccharides" stated — assume it includes substrate starch.
- No part named at all — assume the least favourable interpretation.
Questions about this
Frequently asked
Is fruiting body better than mycelium?
For hericenone content and for avoiding grain filler, yes. But erinacines — arguably the more promising compounds — come from mycelium. The real problem is not mycelium itself; it is mycelium grown on grain where the grain is included in the stated weight.
What is mycelium on grain?
Mycelium cultivated on a sterilised grain substrate, then dried and ground together because the two cannot be separated. The finished powder contains a substantial proportion of grain starch.
Why do labels say polysaccharides instead of beta-glucans?
Because starch is a polysaccharide. Measuring total polysaccharides counts grain substrate and produces a much higher number than measuring beta-glucans specifically. Choosing that measure is a decision, and it tells you something about the product.
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