Reishi: what it is

Reishi is the Japanese name for Ganoderma lucidum and its close relatives, a group of bracket mushrooms that grow on the base and roots of hardwood trees. In Chinese it is lingzhi. The mushroom is kidney shaped, with a hard, glossy, red-brown cap that looks varnished, grading to a pale cream rim when young. It has pores rather than gills, and it is far too woody and bitter to eat as food, which is why it has always been dried, sliced and boiled, or extracted.

This guide covers where reishi grows, how it is farmed and processed, the formats it comes in and how to read a reishi label. It does not cover health claims, because no health claim for any mushroom is authorised in Great Britain.

Where it grows

Wild reishi grows on oak, maple, plum and other hardwoods in temperate forests across Asia, Europe and North America. It fruits in summer and autumn, usually at the base of a living or dying tree or on stumps. Wild specimens are uncommon enough that the supplement market relies almost entirely on cultivated reishi.

How it is farmed

Reishi has been cultivated for decades, first on hardwood logs buried in soil and now mostly on sterilised sawdust blocks or logs in controlled growing rooms. The fruiting body takes several months to form, which is slow compared with lion's mane or oyster mushrooms, and it is harvested when the pale rim has coloured over. Some producers harvest the spores separately, which are sold as "spore powder" or "cracked spore" products, a different thing from the fruiting body.

Most reishi in UK supplements is grown in China, with some from Europe and North America. Origin is a fact a brand can state; we show it where they do.

How it is processed

Because the fruiting body is hard and woody, it cannot be eaten and even powdered reishi is tough to digest. Traditional preparation is a long simmer of dried slices in water. Supplement makers do the equivalent at scale: the dried fruiting body is broken up and extracted with hot water, with alcohol, or with both in turn (a "dual extract"), the liquid is dried and the solids milled into an extract powder. That powder is what goes into capsules.

Some products are instead whole fruiting body powder, simply dried and milled. Those are less concentrated than an extract and the body has to do the extracting. The label should say which. Our label guide explains the difference between powder and extract and what an extract ratio means.

The formats

Capsules

The most common format by far. Extract or powder in a vegetable or gelatine capsule, usually 300 mg to 600 mg each, with a daily count on the pack. Capsules avoid the taste entirely, which with reishi is the main point. The reishi capsules we stock are 500 mg of extract, 90 to a pot, up to three a day.

Powder

Dried fruiting body or extract, loose, stirred into a drink. Reishi powder is dark brown and tastes strongly bitter, so it tends to go into coffee, cacao or a spiced drink rather than water.

Slices and tea

Dried slices of the fruiting body, simmered for 30 minutes to two hours to make a tea. The traditional method and the least processed, but time consuming and very bitter. Not currently on our shelf.

Tinctures

Liquid dual extracts in alcohol, taken by the drop. Not currently on our shelf.

Blends

Reishi also appears as one species in multi-mushroom capsules. In our six mushroom complex it is one sixth of each capsule alongside chaga, cordyceps, lion's mane, shiitake and maitake.

What it tastes like

Bitter. Reishi is among the most bitter things sold as food, with a woody, slightly medicinal flavour that lingers. Brewed as a tea it is dark amber and very astringent. In a capsule you taste nothing, and that is why most people choose capsules. If you want to try the taste, a small amount of powder in strong coffee hides most of it.

Red, black and the other reishi

Traditional sources describe several colours of lingzhi, and some modern products use those names. Red reishi is Ganoderma lucidum or its very close relative Ganoderma lingzhi, and it is the one nearly all supplements use. Black reishi is usually Ganoderma sinense. Other species in the genus, such as Ganoderma applanatum (the artist's bracket), are sometimes sold under the reishi name too. The Latin name on the label is the way to tell which one you are buying, and a label with only "reishi" or "lingzhi" is leaving it open.

Reading a reishi label

• Species. Ganoderma lucidum is the usual one; some products use Ganoderma lingzhi or a mix.
• Part. Fruiting body, mycelium or spore. Fruiting body is the traditional part.
• Powder or extract, and the ratio. Dual extracts (water and alcohol) will usually say so.
• Beta-glucan percentage. If standardised.
• Milligrams per capsule, capsules per pot, daily rate. From these you get days per pot and cost per day.
• Capsule shell and other ingredients.

Reishi at Herbastore

We list reishi on the mushroom supplements shelf, in capsule form and as part of the six mushroom complex, and you can see every capsule we stock under capsules. Each listing shows the amount per serving and cost per serving where the brand gives us the figures.

If you take any medication or have a medical condition, speak to a pharmacist or your GP before adding a supplement. This guide describes the mushroom; it is not advice.