Eating raw button mushrooms from the grocery store is generally safe, but cooking them is almost always the better choice. Raw mushrooms are harder to digest, less nutritious, and certain varieties can cause real problems if eaten uncooked. The answer depends heavily on which type of mushroom you’re talking about.
Common Button Mushrooms Are Low Risk
White button mushrooms, cremini, and portobello mushrooms (all the same species, Agaricus bisporus, at different stages of growth) are the ones most people eat raw, typically sliced into salads. These are safe for most healthy adults to eat uncooked in normal amounts.
You may have heard concerns about agaritine, a naturally occurring compound in these mushrooms that some early studies flagged as a potential carcinogen. Fresh button mushrooms contain roughly 94 to 629 milligrams of agaritine per kilogram, and cooking reduces those levels significantly. However, the cancer concern has largely been walked back. The studies that raised the alarm used synthetic chemical derivatives injected into mice at concentrations far beyond what you’d get from eating mushrooms. Feeding studies using actual mushrooms and mushroom extracts have generally shown no toxicological effects, and results from the earlier mouse studies have not been reproducible in rat models. A review published in the Journal of Functional Foods concluded that agaritine from cultivated button mushrooms poses no known toxicological risk to healthy humans.
So a few raw mushroom slices on your salad won’t hurt you. But there are still good reasons to cook them.
Why Cooking Makes Mushrooms Better
Mushroom cells are surrounded by a tough wall made of chitin, the same material found in insect exoskeletons. Your digestive system doesn’t break chitin down efficiently, which means raw mushrooms pass through you partially undigested. Cooking breaks down that cell wall, making mushrooms easier on your stomach and releasing nutrients your body can actually absorb.
Mushrooms are a solid source of selenium (which helps prevent cell damage), vitamin D (important for cell growth and bone health), and vitamin B6 (which your body uses to form red blood cells). You get more of all of these when the mushrooms are cooked. If you’re eating mushrooms for their nutritional value, eating them raw is shortchanging yourself.
Some Mushrooms Should Never Be Eaten Raw
While button mushrooms are forgiving, several popular varieties are not.
- Morels: Raw morels can make you seriously ill. The CDC investigated a 2023 outbreak in Montana linked to morel mushroom exposure and found that consuming raw morels was more strongly associated with illness than eating cooked or partially cooked ones. The specific toxins in morels aren’t fully identified, but thorough cooking appears to reduce them to safe levels. The CDC’s recommendation is straightforward: morels should always be cooked before eating.
- Shiitake: Eating raw or undercooked shiitake mushrooms can trigger a condition called flagellate dermatitis in susceptible people. It causes distinctive whip-like streaks of red, itchy, raised skin, similar in appearance to a reaction caused by certain chemotherapy drugs. A sugar molecule called lentinan in the mushroom is thought to be responsible, and it breaks down with heat. Cooking shiitake thoroughly eliminates the risk.
- Enoki: Raw enoki mushrooms have been linked to Listeria contamination. In a 2022 outbreak tracked by the FDA, laboratory testing found Listeria in many enoki products sampled, and all five people who fell ill were hospitalized. The FDA and CDC specifically advise people who are pregnant, over 65, or immunocompromised to avoid eating enoki mushrooms raw and to keep them separated from foods that won’t be cooked.
Wild Mushrooms Are a Different Category Entirely
Everything above applies to commercially grown mushrooms bought from a store. Wild foraged mushrooms follow completely different rules. France’s national food safety agency advises never eating any wild mushroom raw, recommending 20 to 30 minutes of cooking in a pan or 15 minutes in boiling water, with the cooking water discarded afterward. This destroys parasites and bacteria that wild mushrooms commonly carry and neutralizes compounds that are toxic when raw but harmless after cooking.
The consequences of getting it wrong with wild mushrooms go far beyond an upset stomach. Poisoning from improperly prepared wild mushrooms can cause severe digestive illness, kidney complications, and liver damage serious enough to require a transplant. Even experienced foragers cook everything they pick.
Reducing Risk If You Eat Them Raw
If you prefer raw mushrooms in salads or as a snack, stick to commercially grown white button, cremini, or portobello varieties. Store them in the refrigerator at 40°F or below, as the FDA recommends for all perishable produce. Give them a gentle rinse or wipe before eating to remove surface dirt and any residual bacteria from handling and packaging.
Keep portions modest. A few slices on a salad are fine, but eating large quantities of raw mushrooms may cause bloating or digestive discomfort simply because of the chitin your gut can’t break down. If you notice gas or stomach upset after eating raw mushrooms, that’s your body telling you it’s struggling with the uncooked cell walls, not a sign of poisoning.
For any other variety, cooking is not optional. It’s the step that makes them safe, digestible, and nutritionally worthwhile.