Shaggy Mane

The short version. Shaggy mane is a tall, white, shaggy-capped mushroom that is eaten young and fresh. Its cap turns to black fluid within hours of picking, so it is a mushroom to cook the same day. The health claims, mainly lower blood sugar, come from mice, rats and laboratory tests; a 2020 review found no human trial of them. [1] The famous "inky cap and alcohol" reaction belongs to a different mushroom, the common inky cap, and whether shaggy mane shares it is not settled by the sources we could read. [1][2][3]

Two separate questions. Eating the mushroom as food is one question (freshness, cooking, allergy, metals). Taking it as a powder or extract is another, and no supplement benefit has been shown in people.

What it is

Coprinus comatus, the shaggy mane or lawyer's wig, is an edible ink-cap mushroom with a tall, shaggy, white cap. [1] As it ages, the gills and cap dissolve into an inky black liquid (the review calls it autolysis, or self-digestion). [1] That is why it is rarely sold in shops and is mostly picked wild or grown at small scale.

Wild mushrooms cannot be safely identified from a description, and this page gives no identification help. Do not identify wild fungi from text or an app. The review we read warns that shaggy mane can be confused with the common inky cap (Coprinopsis atramentaria), which has a similar cap, and that mix-up matters for the alcohol reaction below. [1] We found no other source naming look-alikes. If any wild mushroom was eaten and you are unsure what it was, call Poison Help at 1-800-222-1222 in the US. See mushroom poisoning and urgent help and cooking edible mushrooms safely.

As a food

• Freshness is the rule. The review says fruiting bodies are highly perishable and must be eaten, processed or iced within 4 to 6 hours of collection, and that they break down within 2 days of storage. [1] Use only young, firm, white specimens, and do not keep leftovers.
• Nutrition. The review quotes, per 100 g dry weight, about 11.8 to 29.5 g protein, 49 to 76 g carbohydrate, 1.1 to 5.4 g fat and 368 to 525 kcal, with potassium and phosphorus the main minerals. [1] Fresh mushroom is mostly water, so a cooked portion supplies much less. USDA FoodData Central has no entry for shaggy mane, so there is no official table to compare with.
• Vitamin D. The review did not measure ergosterol (the vitamin D2 precursor) for this mushroom, so we make no vitamin D claim. [1]
• Cooking. The only source-backed rule we found is the freshness limit above. We did not find a shaggy-mane-specific cooking study; the general advice on cooking edible mushrooms safely applies.

The alcohol question (coprine)

Some inky-cap mushrooms contain coprine. In the body coprine is changed into a compound that irreversibly blocks the liver enzyme that clears acetaldehyde, a breakdown product of alcohol, so a drink taken after eating the mushroom causes flushing, headache, nausea and a racing heart. [2][3] This is called a disulfiram-like or "coprinus syndrome" reaction. It is named for the common inky cap, Coprinopsis atramentaria. [2][3] One mushroom-toxin page says symptoms usually start within minutes of eating the inky cap with alcohol, may show up as much as 8 hours before or after drinking, and can recur up to 48 hours later. [3] The 2020 review gives a window of 30 minutes to 3 days. [1]

What do the sources say about shaggy mane itself?

• The 2020 review attributes coprine to the common inky cap, not to shaggy mane, and concludes that shaggy mane does not contain it. But it gives no chemical analysis, and the sentence supporting this is unclear. [1]


• The two other sources we read (a pharmacology review and a toxin page) do not mention shaggy mane at all. [2][3]


• Popular foraging sites disagree, and we did not use them as evidence.

So the honest summary is: the reaction is proven for the common inky cap; for shaggy mane it is not shown, and not firmly ruled out in the sources we read. Because the two look alike and mistakes happen, a cautious reader would not drink alcohol around any wild ink-cap meal. We could not open the original coprine papers listed in the review. This is a general information point, not medical advice; people on disulfiram or other alcohol-aversion medicine should ask a pharmacist.

Traditional use and where it is used

The review describes shaggy mane as a long-used food in China, including as an anti-diabetic food. [1] Traditional use is not evidence that it works, and the research below does not show it.

What research shows

A 2023 snack-bar study used shaggy mane powder and tested glucose release in a laboratory digestion model, not in people; the authors say clinical trials are needed. [4]

Vanadium

Vanadium is a trace metal. Shaggy mane mycelium grown with added vanadium can take up large amounts, and this vanadium-enriched fermented product is what was used in the mouse blood-sugar studies. [1] The same review notes that in one mouse study vanadium taken up by the mushroom reduced body weight, while the fermented product did not significantly. [1] Vanadium compounds are not a proven or safe treatment, and nothing here was tested in people. We did not open the original papers (they are behind a publisher login), so this is second-hand.

Fruiting body, mycelium and grain products

Almost all the food use is the fruiting body. The blood-sugar and vanadium work used fermented mycelium or purified extracts, which are different materials. [1] We found no mycelium-on-grain supplement study for this species. See fruiting body vs mycelium and mycelium grown on grain.

Forms you may see

• Fresh young fruiting body, cooked: the food.
• Dried powder: used as a food ingredient in a 2023 study. [4]
• Extracts, fermented products: used in animal studies only. [1]

Lab data and chemistry

A. What the laboratory literature reports in this mushroom. The Wikidata/LOTUS file we used has no compounds listed for Coprinus comatus (taxon Q275125), so the table comes from a review we read. [5][1] A presence entry means "reported in at least one study of this species", not "present in every product". We did not open the original papers, so no ChEBI or Wikidata IDs were looked up.

B. Measured values. USDA FoodData Central has no entry for shaggy mane. No value below was measured by us or read in an original paper; they are numbers quoted by a 2020 review, and the original papers were not opened.

C. What the numbers do and do not mean.

• Two sources disagree on protein (11.8 to 29.5 against 14.2 g per 100 g dry), and the wide range reflects strain, age at picking, drying and method.


• A lab compound in a mushroom does not show a health effect. The blood-sugar findings are from animals and test tubes.


• Dry-weight figures overstate what a fresh serving gives, because the fresh mushroom is mostly water.


• Metal levels depend heavily on where the mushroom grew: the mercury values above differ about 70-fold between sites. [1]


• No source we read compared fruiting body with mycelium for this species.

Related pages

• Morel
• Chanterelle
• Cooking edible mushrooms safely
• Mushroom poisoning and urgent help