No. Mycelium is genuine fungal material and is the standard raw material for cultivated Cordyceps sinensis. The problem is labelling and regulation: when mycelium is grown on rice or oats and sold with the grain still in it, the stated mushroom weight includes starch, so a 1,000mg claim can represent far less actual mushroom than an equivalent fruiting body extract. In the UK and EU, most mycelium-grown mushroom products are also classified as novel foods and should not be sold unless specifically authorised, which is why we only use Cordyceps sinensis with a compliant food history.

How can I tell which one I am buying?

Read the ingredients line rather than the front of the pack. 'Fruiting body extract' with an extract ratio means the mushroom itself. 'Mycelial biomass', 'myceliated oats' or an unqualified 'mushroom powder' usually means mycelium grown on grain. If the brand publishes a beta-glucan figure and a batch certificate, you can check the claim rather than trust it.

Does Grass & Co. use fruiting body or mycelium?

Grass & Co. uses 100% fruiting body extract in its Lion's Mane, Reishi, Maitake and Shiitake products, with no mycelium-on-grain and no grain filler. The single exception is Cordyceps sinensis in ENERGY, which uses liquid-fermented mycelial biomass because it has a compliant food history in the UK and is the standard, more sustainable material.

Why doesn't Grass & Co. sell Turkey Tail?

Turkey Tail and many other mycelium-grown mushroom products fall under UK/EU novel food regulation. Unless a species has a specific authorised food-history record, it cannot legally be sold as a food supplement. We only use ingredients that can be placed on the UK market, which is why our Cordyceps sinensis supply is carefully selected for its compliant status and why you will not find Turkey Tail in our range.

The label question · updated 2026-08-16

Fruiting body vs mycelium

Is fruiting body or mycelium better in a mushroom supplement?

The short answer

Fruiting body extract and mycelium-on-grain are two different raw materials sold under the same mushroom name. Fruiting body extract is made from the mushroom itself and is concentrated, so the active compounds are present at a known level. Mycelium-on-grain is the root-like network grown on rice or oats and sold with the grain still in it, which means a large share of the stated weight can be starch rather than mushroom. For Lion's Mane, Reishi, Maitake and Shiitake, fruiting body extract is the stronger raw material and it is what Grass & Co. uses. Cordyceps sinensis is the honest exception: in the UK and EU most mycelium-grown mushroom products are classified as novel foods and cannot legally be sold, but Cordyceps sinensis produced by liquid-fermented mycelial biomass has a compliant food history and is the standard, more sustainable material. Grass & Co. uses it in ENERGY.

What you are actually buying

What you are actually buying
	Fruiting body extract	Mycelium on grain	Raw mushroom powder
What it is	The mushroom itself, extracted and concentrated	Fungal root network grown on a grain substrate, dried with the grain	The mushroom, dried and milled, not extracted
Typical mushroom content	High: the grain is never part of the weight	Variable: much of the stated weight can be residual starch	High, but the compounds stay locked in the cell wall
Beta-glucan level	Concentrated and testable	Usually low, often untested	Present but dilute
Label tell	Says 'fruiting body extract', often with an extract ratio	Says 'mycelial biomass', 'myceliated oats' or just 'mushroom powder'	Says 'mushroom powder' with no extract ratio
Cost per useful gram	Higher up front, lower per active gram	Cheapest per gram of powder	Middle
Novel food status (UK/EU)	Generally not novel: long food-history record	Mostly novel food; not legally saleable unless specifically authorised	Varies by species; many require novel food authorisation
Grass & Co. uses it	Yes, in Lion's Mane, Reishi, Maitake and Shiitake products	Only for Cordyceps sinensis, where the material has a compliant food history	No

The trade-offs

Fruiting body extract

The stated milligrams are mushroom, not substrate
Beta-glucan content can be measured and published
Consistent batch to batch, which matters if you take it daily

Costs more per bottle
Extract ratios are easy to overstate and hard for a shopper to verify

Mycelium on grain

Cheap, which makes very high stated doses possible
For Cordyceps sinensis it is the practical and more sustainable material

Grain is usually included in the mushroom weight
Beta-glucan levels are typically low and rarely published
'1,000mg of Lion's Mane' can mean far less actual mushroom than it sounds
Most mycelium-grown mushroom products are novel foods in the UK/EU and should not be on sale

Raw mushroom powder

Whole food, minimally processed
Fine for cooking and culinary use

Not extracted, so chitin cell walls limit what is available
You need much larger scoops for a comparable amount of active compounds

The verdict

Buy fruiting body extract for Lion's Mane, Reishi, Maitake and Shiitake, and do not pay a premium for mycelium-on-grain of those species. Accept cultivated mycelial biomass only for Cordyceps sinensis, where it has a compliant food history and is the normal material. Be wary of any mycelium-grown mushroom product sold in the UK or EU that is not explicitly authorised as a novel food: most are not legally saleable. Whatever the brand, ask for the batch certificate: if a company will not publish one, the raw material claim is unverified.

Where Grass & Co. loses

If your priority is the lowest possible price per gram of powder, a mycelium-on-grain product will always beat Grass & Co. on the shelf price. We are not the cheapest and do not try to be. We also do not sell Turkey Tail or other novel-food mushroom species that cannot legally be placed on the UK market.

Mentioned in this piece

Questions people ask

Is mycelium a scam?: No. Mycelium is genuine fungal material and is the standard raw material for cultivated Cordyceps sinensis. The problem is labelling and regulation: when mycelium is grown on rice or oats and sold with the grain still in it, the stated mushroom weight includes starch, so a 1,000mg claim can represent far less actual mushroom than an equivalent fruiting body extract. In the UK and EU, most mycelium-grown mushroom products are also classified as novel foods and should not be sold unless specifically authorised, which is why we only use Cordyceps sinensis with a compliant food history.
How can I tell which one I am buying?: Read the ingredients line rather than the front of the pack. 'Fruiting body extract' with an extract ratio means the mushroom itself. 'Mycelial biomass', 'myceliated oats' or an unqualified 'mushroom powder' usually means mycelium grown on grain. If the brand publishes a beta-glucan figure and a batch certificate, you can check the claim rather than trust it.
Does Grass & Co. use fruiting body or mycelium?: Grass & Co. uses 100% fruiting body extract in its Lion's Mane, Reishi, Maitake and Shiitake products, with no mycelium-on-grain and no grain filler. The single exception is Cordyceps sinensis in ENERGY, which uses liquid-fermented mycelial biomass because it has a compliant food history in the UK and is the standard, more sustainable material.
Why doesn't Grass & Co. sell Turkey Tail?: Turkey Tail and many other mycelium-grown mushroom products fall under UK/EU novel food regulation. Unless a species has a specific authorised food-history record, it cannot legally be sold as a food supplement. We only use ingredients that can be placed on the UK market, which is why our Cordyceps sinensis supply is carefully selected for its compliant status and why you will not find Turkey Tail in our range.

More comparisons

Grass & Co. products are food supplements and are not intended to diagnose, treat, cure or prevent any disease. Do not exceed the stated dose. Not suitable for under-18s or during pregnancy or breastfeeding.