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Why Shiitake Mushrooms Are Good For You
By Kerri-Ann Jennings, MS, RD
Shiitake mushrooms are one of the most popular mushrooms worldwide.
They are prized for their rich, savory taste and diverse health benefits.
Compounds in shiitake may help fight cancer, boost immunity and support heart health.
This article explains everything you need to know about shiitake mushrooms.
What Are Shiitake Mushrooms?
Shiitake are edible mushrooms native to East Asia.
They're tan to dark brown, with caps that grow between 2 and 4 inches (5 and 10 cm).
While typically eaten like vegetables, shiitake are fungi that grow naturally on decaying hardwood trees.
Around 83% of shiitake are grown in Japan, although the United States, Canada, Singapore, and China also produce them (1).
You can find them fresh, dried, or in various dietary supplements.
Shiitake mushrooms are brown-capped mushrooms used around the world for food and as supplements.
Nutrition Profile of Shiitake Mushrooms
Shiitake are low in calories. They also offer good amounts of fiber, as well as B vitamins and some minerals.
The nutrients in 4 dried shiitake (15 grams) are (2):
- Calories: 44
- Carbs: 11 grams
- Fiber: 2 grams
- Protein: 1 gram
- Riboflavin: 11% of the Daily Value (DV)
- Niacin: 11% of the DV
- Copper: 39% of the DV
- Vitamin B5: 33% of the DV
- Selenium: 10% of the DV
- Manganese: 9% of the DV
- Zinc: 8% of the DV
- Vitamin B6: 7% of the DV
- Folate: 6% of the DV
- Vitamin D: 6% of the DV
In addition, shiitake contain many of the same amino acids as meat (3).
The amount of bioactive compounds in shiitake depends on how and where the mushrooms are grown, stored, and prepared (3).
Shiitake mushrooms are low in calories. They also offer many vitamins, minerals, and other health-promoting compounds.
How Are They Used?
Shiitake mushrooms have two main uses — as food and as supplements.
Shiitake as Whole Foods
You can cook with both fresh and dried shiitake, although the dried ones are slightly more popular.
Dried shiitake have an umami flavor that's even more intense than when fresh.
Umami flavor can be described as savory or meaty. It's often considered the fifth taste, alongside sweet, sour, bitter, and salty.
Both dried and fresh shiitake mushrooms are used in stir-fries, soups, stews, and other dishes.
Shiitake as Supplements
Shiitake mushrooms have long been used in traditional Chinese medicine. They're also part of the medical traditions of Japan, Korea, and Eastern Russia (4).
In Chinese medicine, shiitake are thought to boost health and longevity, as well as improve circulation.
However, many of the studies have been done in animals or test tubes rather than people. Animal studies frequently use doses that far exceed those that people would normally get from food or supplements.
In addition, many of the mushroom-based supplements on the market have not been tested for potency (5).
Although the proposed benefits are promising, more research is needed.
Shiitake have a long history of use, both as a food and in supplements.
May Aid Heart Health
- Eritadenine. This compound inhibits an enzyme involved in producing cholesterol.
- Sterols. These molecules help block cholesterol absorption in your gut.
- Beta glucans. This type of fiber can lower cholesterol.
One study in rats with high blood pressure found that shiitake powder prevented an increase in blood pressure (8Trusted Source).
A study in lab rats fed a high-fat diet demonstrated that those given shiitake developed less fat in their livers, less plaque on their artery walls, and lower cholesterol levels than those that didn't eat any mushrooms (9Trusted Source).
Still, these effects need to be confirmed in human studies before any solid conclusions can be made.
Several compounds in shiitake help lower cholesterol and may reduce your risk of heart disease.
May Boost Your Immune System
Shiitake may also help strengthen your immune system.
This immune effect might be partly due to one of the polysaccharides in shiitake mushrooms (11Trusted Source).
Eating shiitake mushrooms regularly may help boost your immune system.
Contain Compounds With Potential Anticancer Activity
Lentinan has been shown to inhibit the growth and spread of leukemia cells (17Trusted Source).
In China and Japan, an injectable form of lentinan is used alongside chemotherapy and other major cancer treatments to improve immune function and quality of life in people with gastric cancer (18Trusted Source, 19Trusted Source).
However, evidence is insufficient to determine whether eating shiitake mushrooms has any effect on cancer.
Lentinan is a polysaccharide in shiitake mushrooms that may help fight cancer.
Other Potential Benefits
Shiitake mushrooms may also help fight infections and promote bone health.
Promising Antibacterial and Antiviral Effects
As antibiotic resistance is growing, some scientists think it's important to explore the antimicrobial potential of shiitake (21Trusted Source).
That said, while isolated compounds show antimicrobial activity in test tubes, eating shiitake is unlikely to have any effect on viral, bacterial, or fungal infections in people.
May Strengthen Your Bones
Mushrooms are the only natural plant source of vitamin D.
Your body needs vitamin D to build strong bones, yet very few foods contain this important nutrient.
The vitamin D levels of mushrooms vary depending on how they're grown. When exposed to UV light, they develop higher levels of this compound.
However, keep in mind that shiitake provide vitamin D2. This is an inferior form compared with vitamin D3, which is found in fatty fish and some other animal foods.
Compounds in shiitake have antimicrobial properties, though you're unlikely to gain benefits from eating the mushrooms themselves. Shiitake with higher vitamin D levels may improve your bone density.
Possible Side Effects
Most people can safely consume shiitake, although some side effects may occur.
In rare cases, people can develop a skin rash from eating or handling raw shiitake (23Trusted Source).
This condition, called shiitake dermatitis, is thought to be caused by lentinan (24Trusted Source).
Shiitake may cause some side effects, such as skin rashes. Shiitake extract may also cause digestive problems and increased sensitivity to sunlight.
How to Cook With Shiitake
Mushrooms have a distinct umami flavor, which can be especially helpful when making vegetarian dishes.
Shiitake mushrooms are often sold dried. Before cooking, soak them in hot water to soften them.
To select the best specimens, look for ones sold whole rather than sliced. The caps should be thick with deep, white gills.
When cooking with fresh shiitake mushrooms, remove the stems, which remain tough even after cooking. Save the stems in the freezer for making veggie stock.
You can cook shiitake as you would any other mushroom. Here are a few suggestions:
- Sauté shiitake with greens and serve with a poached egg.
- Add them to pasta dishes or stir-fries.
- Use them to make a flavorful soup.
- Roast them for a crispy snack or side dish.
You can cook with either rehydrated, dried, or fresh shiitake mushrooms. They add a delicious, savory flavor to foods.
The Bottom Line
Shiitake have a long history of use, both as a food and a supplement.
While the research on the health benefits of these mushrooms is promising, very few human studies exist.
However, shiitake are low in calories and contain many vitamins, minerals, and bioactive plant compounds.
Overall, they're an excellent addition to your diet.
Reposted with permission from our media associate Healthline.
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