Which mushrooms can you eat raw, and which must be cooked?

The general rule: cook them

As a rule, cook mushrooms before you eat them. Mushroom cell walls are made of chitin, which people digest poorly. Cooking softens it and makes mushrooms easier to digest. In an article for Mycena News, the bulletin of the Mycological Society of San Francisco (republished on MykoWeb), David Campbell explains that many edible mushrooms contain irritants that are destroyed by heat, and can cause trouble when eaten raw or barely cooked.

This doesn't mean cooking can make a poisonous species safe: the toxins in the death cap survive cooking. Cooking prevents the discomfort an edible species can cause raw; it doesn't fix a misidentification.

Button mushrooms: fine raw, with a footnote

The button mushroom (Agaricus bisporus) is the mushroom most often eaten raw, in salads and starters. It contains a natural compound called agaritine. High-dose animal studies have shown harmful effects; what it means for people is not established.

According to a study from the Institute of Chemical Technology in Prague, five minutes of boiling moves about half of the agaritine into the cooking water, microwaving cuts it to a third, and storage time and conditions reduce it further. Campbell points out that agaritine is partly heat-stable, so some remains in cooked mushrooms too. In short: eating button mushrooms raw is common practice, and cooking lowers the agaritine.

Morels: never raw

Morels should never be eaten raw. In 2023, 51 people fell ill after eating morels at a restaurant in Montana, USA; three were hospitalised and two died. The CDC report found that eating raw morels was more strongly linked to illness than eating ones that were at least partly cooked. It advises cooking morels before eating; the substance responsible is not fully understood.

Cook morels through, not just a quick toss in the pan. For their poisonous look-alike see true morels vs false morels.

Shiitake: undercooked can mean a rash

Eaten raw or undercooked, shiitake can cause a striped, itchy rash in some people, known as shiitake dermatitis. According to DermNet it usually appears about a day after the meal, clears on its own within a few weeks, and affects around 2% of people who eat shiitake raw or lightly cooked. The suspected culprit, lentinan, breaks down with heat, so the rash isn't seen with thoroughly cooked shiitake.

Rather than slicing raw shiitake over ramen, cook it properly in the broth or the pan.

Enoki: cook it for Listeria

Enoki should be cooked thoroughly because of the risk of Listeria. Because enoki is thin and delicate, it often goes into soups and salads raw at the last minute. After Listeria outbreaks linked to enoki in the US, the CDC advises everyone to cook enoki thoroughly and keep raw enoki away from foods that won't be cooked. People who are pregnant, aged 65 or over, or have weakened immune systems should not eat raw enoki at all.

Wild mushrooms

Wild mushrooms should always be cooked. Campbell's article notes that morels, oyster mushrooms and hedgehog mushrooms are likely to make you ill raw, and that chanterelles irritate the stomach when raw. Mushrooms picked in the wild also carry soil and insects. Even once you're certain of the species, cook wild mushrooms thoroughly.

For prep, see how to clean mushrooms; for a simple way to cook them, our mushroom sauté.