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Writer's picturePlantzMatter

Oxalate Content Levels in Mushrooms Differ

People worldwide love mushrooms for their flavours, textures, and health benefits. There are many types of mushrooms, but how much oxalate do they have? Oxalate levels in mushrooms vary depending on the type of mushroom. I have prepared a table to help you watch your oxalate intake.

variety of fresh mushroom on black background

Soluble and Insoluble Oxalate What's the Difference?


  1. Soluble Oxalate: This type of oxalate dissolves in water. Because of this soluble oxalate can be absorbed into the blood from the gut. This can be bad for sensitive individuals. If absorbed by the body, soluble oxalate can contribute to kidney stone formation.


  1.  Insoluble Oxalate: This form does not dissolve in water. So, it passes through the digestive system without being absorbed. Insoluble oxalates are less likely to form kidney stones. They exit the body with waste.


The main difference is this: the body can absorb soluble oxalates. They can lead to health issues like kidney stones. In contrast, the body does not absorb insoluble oxalates. It simply excretes them.


The deposition of calcium oxalate happens when oxalate from mushrooms mixes with calcium in your body. This can form crystals. These crystals can build up in the kidneys and may lead to kidney stones or damage. Eating too many mushrooms, especially supplements like powders, increases this risk.


But, consuming calcium-rich foods with oxalate-rich foods can help. Calcium-rich foods can reduce the risk of deposition of calcium oxalate. When eaten together, the calcium binds with the oxalate in the gut. They form a compound that the body can remove before it reaches the kidneys. This stops the crystals from forming.


Oxalate Content in Mushrooms


Mushrooms are generally considered to have moderate levels of oxalates. The oxalate content in mushrooms can vary based on the type of mushroom. Some types may have less or more. Those on a low-oxalate diet must be aware of these differences to manage their intake.


Unfortunately, there is very little literature on the oxalate content of mushrooms. One publication titled Soluble and insoluble oxalate content of mushrooms found the following:


  • The total oxalate content in raw, commercially grown mushrooms ranged between 58.9 to 104.1 mg per 100 grams dry mass.


  • After cooking, these values ranged from 48.9 to 124.6 mg per 100 grams dry mass, indicating that cooking can affect oxalate levels.


  • Wild mushrooms contained only soluble oxalates, ranging from 29.3 to 40.2 mg per 100 grams dry mass in their raw state. Cooking slightly reduced the soluble oxalate content.


The study's information on mushrooms is useful. It's relevant for those on a low-oxalate diet. Here's what the research means:


  1. Variability in Oxalate Content: The study shows that farmed and wild mushrooms have varying levels of oxalates. Mushrooms can contain both soluble and insoluble oxalates. Variability means the oxalate intake from eating mushrooms can differ. It varies based on the type of mushroom and how it's prepared.


  1. Impact of Cooking: The study shows that cooking methods can alter the oxalate content in mushrooms. Cooking lowers soluble oxalate. But, in some cases, it raises total oxalate. People on a low-oxalate diet must consider how they prepare mushrooms.


  1. Choice of Mushrooms: Wild mushrooms contain soluble oxalates, which the body absorbs. Their oxalate levels were somewhat lower. So, they might be a better choice for those on strict low-oxalate diets. This is especially true if they are prepared in ways that further reduce oxalate levels. Be sure you know what you're doing and choose edible mushrooms as wild mushrooms can be poisonous!


  1. Comparing Oxalate Levels: Mushrooms can have low levels of oxalates when compared to other common vegetables. This could make mushrooms safer for a low-oxalate diet. But, portion sizes and prep methods must control oxalate intake.


  1. Diet Planning: People on low-oxalate diets must watch not just the type of food but also how it's prepared. Knowing specific details, like the study's data, helps you make informed diet choices. These choices align with your health needs.


Oxalate Content in Different Mushrooms 


Please research and speak to a medical professional before making dietary changes. I have listed the sources I use in the Resource Library. I am not a medical practitioner, just someone trying to raise awareness.


Mushrooms contain varying levels of oxalate depending on the type. However, the preparation and processing of mushrooms can influence their oxalate content.

Here is an example of the varying oxalate content.


The OHF has some actual figures:


  • Mushrooms, Variety, boiled or canned 1 mg per 100 grams

  • Mushrooms, Variety, dried, 76 mg per 100 grams


The UIC:


  • Mushroons: 1 mushroom Little or None 0mg (but it doesn't give information on multiple)


In the example, preparation plays an important role. Water-prepared mushrooms are much lower than those that are more concentrated through the removal of water.

Here's how different mushroom product types can relate to oxalate levels:


1. Fresh Mushrooms


Fresh mushrooms oxalate levels vary among types. Morels, shiitakes, and chanterelles have higher oxalate levels. It's important to consume these mushrooms fresh and in moderation.


2. Dried Mushrooms


Drying mushrooms doesn't change oxalate content per gram. But, you may use more than fresh which means more oxalate. Keep this in mind for oxalate management.


3. Powdered Mushrooms


Powdered mushrooms are potent, packing more oxalates in less. Adding a bit can hike your oxalate intake. If oxalates worry you, go easy on mushroom powders.


Tips for Managing Oxalate Intake from Mushrooms


  • Variety Selection: For lower oxalate levels, pick mushrooms like button mushrooms.

  • Serving Size: Watch out for portion sizes, especially with dried or powdered mushrooms.

  • Culinary Methods: Certain cooking methods, such as boiling, can lower oxalate levels. Oxalates can seep into the cooking water. Boiling is more effective for vegetables than mushrooms. Mushrooms are rarely boiled.



Why You Should Always Cook Your Mushrooms


Besides reducing oxalates you should cook your mushrooms. Cooking mushrooms is important for several key reasons:


  1. Safety: Raw fungi can be dangerous. Cooking mushrooms can kill harmful microorganisms and bacteria. Cooking reduces the risk of foodborne illnesses. This is particularly relevant for wild mushrooms, which may have been exposed to various contaminants in the environment.

  2. Digestibility: Cooking breaks down tough cell walls, making mushrooms easier to digest.

  3. Taste and Texture: It enhances their natural flavours and improves texture.

  4. Nutrition: Heat increases the availability of some nutrients and reduces antinutrients.

  5. Versatility: Cooked mushrooms can be used in a wide variety of dishes, adding rich flavour.


Potential Health Benefits of Mushrooms


Mushrooms are still worth keeping on the menu because they have many health benefits:


  • Rich in Nutrients

  • Antioxidant Properties

  • Immune System Support

  • Heart Health

  • Weight Management

  • Cancer Prevention

  • Mental Health

  • Gut Health

  • Blood Sugar Regulation

  • Bone Health


Potential Health Risks of Mushroom


Mushroom consumption comes with risks. Long-term ingestion of 'medicinal mushrooms' through implementation can cause health issues.


Acute oxalate nephropathy is a sudden drop in kidney function. The buildup of oxalate crystals causes it in the kidney tubes. This can happen when oxalate levels in the body greatly increase. This increase is often due to eating many oxalate-rich foods or substances. These include certain supplements. Or, it can result from conditions that make oxalate or reduce its removal.


Chaga Mushroom Induced Oxalate Nephropathy


Chaga mushrooms have oxalates. They add a moderate amount to the diet. Changa tea is high in oxalate. As supplements like powders or extracts, Chaga can deliver a much higher oxalate concentration. This is problematic. These supplements can significantly increase the body's total oxalate load. Chaga mushrooms have the potential to harm, especially in concentrated forms.


Case Study of Supplement-Associated Oxalate Nephropathy


Oxalate nephropathy is a kidney condition caused by the buildup of oxalate crystals in the kidneys, leading to inflammation and potential kidney failure. It can result from high dietary oxalate intake, genetic disorders, or conditions that increase oxalate production.


In the article Chaga mushroom-induced oxalate nephropathy that clinically manifested as nephrotic syndrome: A case report A 69-year-old man developed acute kidney injury (AKI). He had symptoms of nephrotic syndrome. He developed them after eating Chaga mushroom powder and vitamin C daily for three months. His condition required hemodialysis.


High Levels of Oxalates and Kidney Stones 


A kidney biopsy showed acute tubular injury and calcium oxalate crystals. This finding confirmed acute oxalate nephropathy and minimal change disease. The cause was supplement-associated oxalate nephropathy. Primarily chaga mushroom-induced oxalate nephropathy.


Treatment with high-dose steroids improved his kidney function within a month. This case shows the risks of dietary supplements like Chaga mushrooms. They are high in oxalates. It highlights the need to carefully consider supplement ingredients.


Supplementation Link to Acute Oxalate Nephropathy


Acute oxalate nephropathy happens when oxalate crystals quickly build up in the kidneys. This can occur if someone eats lots of oxalates over a short time. In the context of Chaga mushroom supplements:


  • High Oxalate Intake: If someone uses Chaga supplements a lot, especially in concentrated forms, their oxalate levels can spike. This is more pronounced with dietary intake from whole foods. Supplements can bypass the natural moderation of whole food.



  • Kidney Impact: The kidneys filter out waste and excess substances. They now face a sudden onslaught of oxalates. The oxalates can crystallize in the kidney tubules. This can lead to blockages and damage to kidney tissue.


  • Symptoms and Risks: This rapid development can cause symptoms. They include reduced urine output and swelling, which shows kidney problems. If not addressed, it can lead to more severe kidney damage or even acute kidney failure.


  • Consult Healthcare Providers: Don't change your diet or start supplementation without approval from medical providers. This is especially important for people with kidney issues. It's also key for those at high risk for kidney stones.


Conclusion


For those watching oxalate intake, knowing the levels in mushrooms helps. Mushrooms, are moderately high in oxalates but have good nutritional value. Consult a healthcare provider for tailored advice on oxalate-related health issues. Choose mushrooms and veggies for a balanced diet.


If you have a sensitive stomach, it could be worth investigating FODMAPs in mushrooms.


To find out more about oxalate in greens, read Arugula Oxalates Rocket. Thank you for reading.



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