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Can Oyster Mushrooms Make You Sick?

Can Oyster Mushrooms Make You Sick

Oyster mushrooms are smoothly textured with an attractive cap.

They are one of the most popular varieties in the world, enjoyed by millions worldwide.

The broad stem that widens as it joins the cap is the most desirable part of an oyster mushroom.

Oyster mushrooms need to be boiled for at least ten minutes before eating to ensure that the poisonous toxin orellanine is destroyed.

This toxin causes a rare illness called orellanine poisoning. 

Oyster mushrooms are a delicious and healthy addition to many dishes and are commonly found in grocery stores.

However, they can also make you sick if they are inadequately cooked.

People who eat oyster mushrooms without cooking them can suffer from symptoms such as:

  • Nausea and vomiting
  • Stomach pain
  • Diarrhea
  • Weakness
  • Headaches
  • Fever
  • Joint aches
  • Flu-like symptoms

Pleurotus pulmonarius, Pleurotus ostreatus, and Pleurotus populous belong to the Pleurotaceae family, together known by the common name, oyster mushrooms.

In 1775, Dutch scientist Nikolaus Joseph Freiherr von Jacquin first documented and classified oyster mushrooms; in 1871, German mycologist Paul Kummer reclassified them as a fungus taxonomy.

Oyster mushrooms have thrived in wild forests throughout Europe, Asia, and North America since prehistoric times. Oyster mushrooms are neither poisonous nor hallucinogenic.

The entire body from the stem to the cap may be eaten.

Their name comes from the fact that they resemble freshly shucked oysters, both in appearance and taste.

They develop on dead and decaying wood, such as dying coniferous and deciduous tree trunks, in tropical and temperate woods.

They prefer to be kept out of direct sunlight.

Oyster mushrooms come in a variety of sizes, from medium to enormous, with caps that range from 5 to 25 cm in diameter.

Its fan-shaped caps are large and curved, with wavy and lobed edges as it matures.

Oyster mushrooms come in many hues, ranging from dark gray to light brown, pink, and yellow.

Oyster mushrooms, like shiitake and button mushrooms, are among the most cultivated mushrooms in the world, with flavors that complement a variety of cuisines.

These mushrooms have been linked to several medical benefits.

Oyster mushrooms contain antioxidants that have been proven to protect against free radicals and lower the risk of serious illnesses such as heart disease and cancer.

Can oyster mushrooms cause stomach pain?

Can oyster mushrooms cause stomach pain

To eliminate the potentially fatal poison orellanine, oyster mushrooms must be simmered for at least ten minutes.

This toxic substance produces a rare ailment known as orellanine poisoning.

One of the symptoms of orellanine poisoning is stomach pain.

Orellanine poisoning is a type of mushroom poisoning that is caused by the ingestion of orellanine, a toxic compound found in several species of mushrooms, like the oyster mushroom.

Symptoms of orellanine poisoning include gastrointestinal problems, such as abdominal pain and vomiting, and kidney damage. In severe cases, orellanine poisoning can lead to death.

Other symptoms of orellanine poisoning include:

  • Diarrhea
  • Weakness
  • Headaches
  • Flu-like symptoms
  • Fever
  • Joint pain
  • Nausea and vomiting

In addition, oyster mushrooms go bad quickly and can cause illness if a bad mushroom is used in your dish.

To check if the oyster mushroom is still good to be eaten:


Look for discoloration.

Oyster mushrooms are generally light gray or brown, although variety affects color.

If the mushrooms darken considerably after being picked or purchased, or if they develop dark marks or flaws, they have gone bad.


Rub the mushrooms to feel the texture.

Fresh oyster mushrooms are dry.

If the feeling of wetness or slime persists, it’s an indication that the fungus is bad.


Squeeze the mushroom gently. See how to do that properly in the video below

The skin of a fresh mushroom will be firm, but the flesh will be soft and spongy.

It’s gone bad if the mushroom is hard, brittle, or dry.


Smell the mushroom.

If your mushroom has an ammonia-like scent, it’s time to throw it away.

Do oyster mushrooms cause gas?

Do oyster mushrooms cause gas

Yes, eating oyster mushrooms can cause gas.

Like many other types of mushrooms, oyster mushrooms contain a type of sugar called glucose.

This sugar is fermented in the body by probiotics, the healthy bacteria in the gut.

Feeding the probiotics can produce gas as a by-product.

The specific type of bacteria that breaks down glucose to produce gas is called saccharomyces.

This genus includes several types of yeast, including baker’s yeast, or saccharomyces cerevisiae.

When higher concentrations of oyster mushrooms are eaten, more saccharomyces will be present in the gut, leading to increased production of gas.

The amount of time it takes for a portion of food to cause gas in the gut varies from person-to-person and is dependent upon factors such as:

  • what other foods have been eaten at the same time
  • how much has been eaten
  • age and health of the individual
  • an individual’s metabolism which will determine how quickly saccharomyces can break down glucose.

For example, some people notice that eating mushrooms causes gas after only a short period of time like an hour, while others can eat them without noticing any side effects.

In addition, folks with IBS (Irritable Bowel Syndrome) might be more sensitive to oyster mushrooms and produce more gas.

Eating raw oyster mushrooms can cause even more gas than when they are cooked.

To reduce the amount of gas that is produced when eating oyster mushrooms, you should cook them thoroughly before consuming them.

You can also try chopping or grinding them finely before swallowing them to help to break down the glucose in the body more quickly.

Don’t worry, flatulence is normal, and most people will not experience any negative symptoms.

If you’re concerned about the amount of gas that could be produced when eating oyster mushrooms, talk to your doctor or a nutritionist for further advice and support.

Can you eat too many oyster mushrooms?

Can you eat too many oyster mushrooms

Yes, it is possible for people to eat too many oyster mushrooms.

Oyster mushrooms contain a type of sugar called glucose.

When the body breaks this sugar down into energy it makes gas as a by-product.

If you eat an excessive amount of oyster mushrooms, this gas may build up in the blood and you may get sick.

Although cases of poisoning from eating oyster mushrooms are extremely rare, there have been several documented cases in which people have suffered serious illness due to having eaten too many oyster mushrooms.

Symptoms include:

  • tingling lips
  • tingling fingers
  • tingling toes
  • slurred speech
  • sleepiness
  • incoherent speech
  • lack of coordination

In addition, mushroom allergies affect about 2% of the world’s population.

It is not as common as other food allergies, but it can be serious.

Symptoms of a mushroom allergy include hives, swelling of the lips, tongue, or throat, and difficulty breathing.

Oyster mushrooms are common type of edible mushrooms. They can be found in grocery stores and Asian markets.

Oyster mushrooms come in several varieties, but their use is often interchangeable.

Oyster mushroom allergies are also generally interchangeable; however, you should always ask the grocer or the person who harvested them whether they were exposed to other kinds of mushrooms.

Some people are neither allergic or sensitive to mushrooms, but they cannot digest them very well.

They have what is called mushroom intolerance.

They can digest fungi that are closely related to mushrooms, like morels and chanterelles.