Lion's Mane Mushroom: The Shaggy Fungus That's Illegal to Pick in Britain
If you're lucky enough to spot a lion's mane mushroom in a British wood, usually high on an old beech in somewhere like the New Forest, you'll see something that barely looks like a mushroom at all. It has no cap and no gills, just a football-sized cascade of soft white spines hanging from the trunk like a frozen waterfall.
Admire it, photograph it, and leave it exactly where it is. In the UK, lion's mane (known here as bearded tooth) is so rare that it's one of only four fungi given the highest level of legal protection under the Wildlife and Countryside Act 1981. Picking one can bring a fine of up to £5,000, and people have been investigated for doing it.
Travel to China and the same mushroom is something else entirely: dinner. There it's called hou tou gu (猴头菇), the "monkey head mushroom". It's grown on farms, sold dried in markets, simmered into soups, and prized for a delicate flavour that cooks often compare to crab or lobster. Its meaty texture has even earned it the nickname "vegetarian meat".
It's a mushroom that reminds every culture of a different animal: a lion's mane in English, a monkey's head in Chinese, and a hedgehog in Latin, where erinaceus means exactly that. Most of all, it has become one of the most researched and talked-about mushrooms in the world.
What is lion's mane used for?
A food that became a medicine (and back again)
In China, lion's mane sits in the category of "medicine-food" ingredients: foods also valued for their effect on wellbeing. In Chinese food therapy it's traditionally associated with the Spleen and Stomach, which in TCM terms means digestion and nourishment. It's also traditionally regarded as calming. It's a gentle, everyday mushroom, cooked into chicken soups with other tonic ingredients rather than reserved for special prescriptions.
It's an interesting twist that, in China, lion's mane has long been thought of as a stomach mushroom, while in the West it's become known almost entirely as a brain mushroom. Both reputations come from the same shaggy fungus. They just reflect different traditions asking different questions.
Why scientists got interested
The Western reputation comes from chemistry. Lion's mane contains two families of compounds found almost nowhere else:
- Hericenones: found in the fruiting body, the shaggy part you'd see on a tree.
- Erinacines: found in the mycelium, the network of thread-like roots that grows through the wood.
In laboratory and animal studies, both groups have been found to stimulate the production of nerve growth factor, a protein involved in the growth and maintenance of nerve cells. That's what put lion's mane on the map. However, the great majority of this research has been carried out in test tubes and animals, not people.
What studies in people have found
Human research is newer and smaller. One of the most interesting studies is a 2023 pilot trial from UK researchers involving 41 healthy adults aged 18 to 45. An hour after a single dose, the lion's mane group was quicker on a classic attention test than the placebo group. After four weeks there was a trend toward lower self-reported stress, though it fell just short of statistical significance. The researchers called their findings tentative, noted some results showed no effect, and stressed that the sample was small. A separate 2025 study in healthy young adults found no clear effect on thinking skills after a single dose.
That's the honest picture: genuinely intriguing, but still early. It's why lion's mane is one of the most actively studied mushrooms around right now, and why we'd rather explain the research than overstate it.
Why we chose lion's mane for QiMycology
It's where QiMycology began. Our founder, Toni, first came across lion's mane at university, and wanted to understand what it actually was. That curiosity led her to a TCM doctor, deeper into the Chinese tradition behind mushrooms like this one, and eventually to the suppliers in China who make our blends today. In a real sense, every QiMycology product started with this mushroom.
It's the centrepiece of our daytime blend. Qi Adaptogen is our daytime blend, and lion's mane leads it. It's the largest ingredient in the blend, at 1,200 mg per serving.
It works within a team. Lion's mane isn't asked to do everything on its own. Astragalus is TCM's foundational tonic root. Schisandra is the "five-flavour" berry of classical Chinese formulas, and Rhodiola is a root from cold, high places. Each ingredient has a distinct role, which is the TCM way of building a formula, and the reason we make blends rather than single-mushroom pouches.
It bridges two worlds. Lion's mane is both an old Chinese medicine-food and the subject of modern scientific study, which makes it a natural fit for a brand that wants to make traditional knowledge understandable to a modern audience.
What the research does and doesn't show
Nerve growth factor, explained
Nerve growth factor (NGF) is a protein the body already makes. It's involved in the growth and maintenance of certain nerve cells. NGF itself is a large molecule that doesn't easily pass from the bloodstream into the brain, so researchers have looked for small molecules that might encourage the body to make more of it. Hericenones and erinacines are small molecules, which is why they attracted attention.
The picture is less tidy than many websites suggest. Early laboratory studies reported that some hericenones increased NGF production in mouse cells, but a 2008 study in human brain-derived cells (Mori and colleagues, Biological and Pharmaceutical Bulletin) found that purified hericenones did not increase NGF gene activity, while a whole lion's mane extract did. Erinacines have more consistently been linked to NGF in cell and rodent studies. All of this is preclinical work: cells in a dish, and animals. It shows the compounds are biologically interesting. It doesn't show that eating lion's mane, or taking a supplement, changes NGF in a human brain.
What isn't known yet
- Whether taking lion's mane changes NGF in the human brain.
- Which preparation (fruiting body, mycelium or both), and what amount, would matter.
- What happens with long-term use. Human studies so far are small and short.
That's why "regrows your brain", a claim you'll see online, goes far beyond the evidence.
Safety
Lion's mane has a long history as a food, but there's little formal safety research on concentrated supplements. Avoid it if you're allergic to mushrooms. There isn't enough information on pregnancy or breastfeeding, so it's sensible to avoid supplements then. If you take prescription medication or have a health condition, check with your GP or pharmacist first.
Comparing lion's mane products
- Fruiting body, mycelium or both? This tells you which compound group (hericenones or erinacines) you might expect.
- Powder or extract? If there's a ratio or a percentage, check what it actually measures.
- Amount per serving. Compare per serving, not the headline weight of the pack.
- The claims. Be wary of any product page that turns lab or animal findings into a promise about your brain.
For the full checklist, see How to Read a Mushroom Supplement Label.
Frequently asked questions
Why is it called lion's mane? The cascade of long white spines looks like a shaggy mane. In Chinese it's the "monkey head mushroom", and its Latin name, Hericium erinaceus, refers to a hedgehog. In the UK it's also known as bearded tooth.
Can I forage lion's mane in the UK? No. It's protected under Schedule 8 of the Wildlife and Countryside Act 1981, and picking or damaging it in the wild is a criminal offence. The lion's mane used in food and supplements is cultivated, not wild-picked.
What does lion's mane taste like? Mild, slightly sweet and savoury, often compared to crab or lobster. Fresh, cultivated lion's mane can be sliced and pan-fried like a steak. It's increasingly available from specialist mushroom growers in the UK.
What's the difference between fruiting body and mycelium? The fruiting body is the visible, shaggy mushroom; the mycelium is the root-like network it grows from. They contain different compounds (hericenones in the fruiting body, erinacines in the mycelium), so it's worth checking which part a supplement uses.
How is lion's mane used in traditional Chinese practice? Mostly as a food. It's simmered into soups and stews and traditionally associated with digestion and a settled mind, rather than prescribed as a strong medicine.
Is lion's mane suitable for everyone? Avoid it if you're allergic to mushrooms. If you're pregnant or breastfeeding, have a medical condition or take any regular medication, check with your GP or pharmacist first.
A mushroom with many faces
Lion's mane has lived several lives: a rare, protected treasure in British woodland, a much-loved delicacy in Chinese kitchens, and one of the most closely studied mushrooms in modern research. Few ingredients have travelled so far between tradition and science.
For us, it's also personal. It's the mushroom that started QiMycology, and it's the centrepiece of Qi Adaptogen, our daytime blend. Each serving contains 1,200 mg of Lion's Mane, alongside 1,000 mg of Astragalus, 500 mg of Schisandra and 300 mg of Rhodiola. Our supplier has confirmed our Lion's Mane extract comes from the fruiting body.