Lion's Mane and the Brain: Hericenones, Erinacines and NGF Explained

Lion's Mane contains two families of compounds studied for brain effects. Hericenones come from the fruiting body. Erinacines come mainly from the mycelium. Both stimulated nerve growth factor (NGF) production in cell or animal studies. Whether eating Lion's Mane raises NGF in the human brain has not been shown.

This article explains the chemistry behind the "brain health" label, and why the part of the fungus you buy matters.

What Is Nerve Growth Factor, and Why Does It Matter?

Nerve growth factor is a protein that helps certain nerve cells survive, grow and maintain their connections. It belongs to a family called neurotrophins. Because NGF itself is a large protein, it does not easily pass from the bloodstream into the brain. That is why researchers became interested in small molecules that might prompt brain cells to make more NGF on their own.

Lion's Mane (Hericium erinaceus) became a candidate in the 1990s. That is the origin of nearly every "NGF" claim you will see on a label.

Hericenones vs Erinacines: Where Are They Found?

Hericenones. In 1991, a Japanese team isolated hericenones C, D and E from the fruiting body, the part we recognise as the mushroom. They reported that these compounds stimulated NGF synthesis in cultured cells (Kawagishi et al., Tetrahedron Letters, 1991).

Erinacines. In 1994, the same group isolated erinacines A, B and C from the mycelium, the thread-like root network. They described them as strong stimulators of NGF synthesis (Kawagishi et al., Tetrahedron Letters, 1994).

The picture has since become more complicated. A 2008 study found that a Lion's Mane extract raised NGF gene activity in human astrocytoma cells, and that mice fed 5% Lion's Mane powder for seven days had higher NGF gene expression in the hippocampus. Yet, in the same cell model, purified hericenones C, D and E did not raise NGF. The authors concluded that the active compounds in their extract were not hericenones (Mori et al., Biological and Pharmaceutical Bulletin, 2008).

A 2018 review noted that, among the known compounds, only erinacine A had confirmed pharmacological actions in the central nervous system of rats (Li et al., Behavioural Neurology, 2018). So the compound most discussed on fruiting-body labels is not the one with the strongest animal evidence.

From Cell Dish to Human Brain: What Is Missing?

Almost all of the NGF work is preclinical. Several gaps separate it from a claim about people:

• Dose. Cell studies apply purified compounds directly to cells. We do not know how much of each compound reaches the human brain after eating the mushroom.
• Absorption. Human data on how hericenones and erinacines are absorbed and distributed are scarce.
• What trials measure. Human trials measure cognitive test scores, not brain NGF. A score change cannot confirm the NGF mechanism.
• Animal models. Findings in rats or mice with induced brain injury often fail to translate to people.

The human trials that exist are small and used different products. One used fruiting body powder, another erinacine A-enriched mycelium. Our article on the cognitive spectrum of Lion's Mane covers the broader claims, and our piece on myelin covers another preclinical line of research.

Fruiting Body or Mycelium: What Should a Label Say?

Because the two compound families sit in different parts of the fungus, the product form matters.

• Fruiting body products contain hericenones and the mushroom's polysaccharides. They are the traditional food form.
• Mycelium products may contain erinacines. However, mycelium is often grown on grain, and the finished powder can include leftover substrate. Erinacine content varies widely between strains and growing methods.
• Extracts depend on the solvent. Hot water pulls out polysaccharides. Alcohol pulls out more of the smaller, fat-soluble compounds.

A useful label states the species, the part used (fruiting body or mycelium), the extraction method, and, if a compound is claimed, a tested amount. "Erinacine-rich" without a number tells you little.

For transparency: our Lion's Mane is sold as whole dried fruiting bodies. That means it is the hericenone-containing form, not an erinacine-standardised mycelium, and we make no NGF or cognitive claim for it. For how Lion's Mane fits among other functional mushrooms, see our overview of natural mushroom supplements.

Safety and Who Should Be Careful

Lion's Mane is eaten as a food in many countries. A 2025 systematic review lists stomach discomfort, headache and allergic reactions as reported side effects (Menon et al., Frontiers in Nutrition, 2025).

• Avoid it if you are allergic to mushrooms.
• Avoid supplement amounts during pregnancy and breastfeeding, as no safety data exist.
• If you take regular medication, ask your doctor or pharmacist first. Interaction studies are lacking.
• If you notice memory or nerve symptoms, see a doctor rather than self-treating.

Frequently Asked Questions

What are hericenones and erinacines?

They are two families of compounds found in Lion's Mane. Hericenones were isolated from the fruiting body and erinacines from the mycelium. Both stimulated nerve growth factor synthesis in laboratory studies.

Does Lion's Mane increase NGF in humans?

This has not been shown. The NGF findings come from cell and animal studies. Human trials have measured cognitive test scores, not nerve growth factor in the brain.

Is fruiting body or mycelium better?

They are different materials. Fruiting bodies contain hericenones, while erinacines are found mainly in mycelium. Neither has been proven better in people, so a label should state which part is used.

Do hericenones stimulate NGF?

A 1991 study reported that they did in cultured cells, but a 2008 study found that purified hericenones C, D and E did not raise NGF in human astrocytoma cells.

Is Lion's Mane safe to eat?

It is a culinary mushroom and is generally well tolerated, but stomach discomfort, headache and allergic reactions are reported. Ask a doctor first if you take medication or are pregnant.

This article is for educational purposes only and is not medical advice. It does not replace a consultation with a doctor or pharmacist, especially if you take medication, have a health condition, or are pregnant or breastfeeding.