Shiitake

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Shittake Mushrooms (Lentinus edodes)

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. Shiitake is loaded with several nutritional values.Shiitake are low in calories and offer health-promoting compounds. The bioactive compounds in dried shiitake are fiber, protein, riboflavin, niacin, copper, vitamin B5, and B6. Also includes selenium, manganese, zinc, folate, vitamin D, and essential amino acids. They contain polysaccharides, terpenoids, sterols, and lipids, some of which have immune-boosting, cholesterol-lowering, and anticancer effects. Overall, they’re an excellent addition to your diet. Studies suggest that some of the bioactive compounds in shiitake may protect against cancer and inflammation.

 

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Health Benefits

Shiitake mushrooms have long been used in Traditional Chinese medicine. They’re also part of the medical traditions of Japan, Korea, and Eastern Russia. In Traditional Chinese medicine, shiitake is thought to boost health and longevity, as well as improve circulation. This mushroom has been used as food and in supplement forms. While the research on the health benefits of these mushrooms is promising, very few human studies exist.

May aid heart health

Shiitake mushrooms may boost heart health. They contain three compounds that help lower cholesterol and may reduce the risk of heart disease.

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. 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 lowered cholesterol levels compared to those that didn’t eat any mushrooms.

Shiitake mushrooms have sterol compounds that interfere with the production of cholesterol in the liver. They also contain potent phytonutrients that help keep cells from sticking to blood vessel walls and forming plaque buildup. This helps maintains healthy blood pressure and improves circulation.

A study conducted at Tohoku University in Japan found that shiitake mushrooms prevented blood pressure increases in hypertensive rats. Shiitake feeding resulted in a decrease in VLDL and HDL cholesterol, whereas maitake mushroom feeding caused a decrease in VLDL cholesterol only.

May boost your immune system

Eating Shiitake regularly may also help strengthen your immune system and combat many diseases by way of providing important vitamins, minerals, and enzymes. This immune effect could be due to the polysaccharides in this mushroom. People’s immunity tends to weaken with age. 

A 2015 study published in the Journal of the American College of Nutrition evaluated 52 healthy males and females, aged 21–41 years, to determine if shiitake mushrooms could improve human immune function. The study involved a four-week parallel-group trial that involved participants consuming either 5 or 10 grams of mushrooms daily. The results suggest that consuming mushrooms improved cell effector function and improved gut immunity. There was also a reduction of inflammation due to mushroom consumption.

Another study gave people two dried shiitake daily. After one month, their immune markers improved and their inflammation levels dropped. While people’s immune systems tend to weaken with age, a mouse study found that a supplement derived from shiitake helped reverse some age-related decline in immune function.

Contains compounds with potential anticancer activity

Polysaccharides in shiitake mushrooms may also have an anti-cancer effect. Research suggests that shiitake mushrooms help fight cancer cells and the lentinan in shiitake helps heal chromosome damage caused by anticancer treatments. This suggests shiitakes are potential cancer-fighting foods.

For example, the polysaccharide lentinan which is a polysaccharide in shiitake may help fight cancer and tumors by activating your immune system. Lentinan has been shown to inhibit the growth and spread of leukemia cells.

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.

A 2006 study published in the Journal of Alternative and Complementary Medicine investigated the potential roles of an ethyl acetate fraction from shiitake mushrooms. The study involved two human breast carcinoma cell lines, one human nonmalignant breast epithelial cell line, and two myeloma cell lines. The results suggest that shiitake mushrooms were able to inhibit growth in tumor cells with their mycochemical value. Shiitake mushroom successfully induced apoptosis, the process of programmed cell death.

Shiitake mushrooms may also help fight infections and promote bone health.

  • Antibacterial and antiviral effects: Several compounds in shiitake have antibacterial, antiviral, anti-parasitic, and antifungal effects. Today antibiotic resistance is growing quickly and some scientists think it’s important to explore the antimicrobial potential of shiitake mushrooms.
  • May strengthen your bones: Mushrooms are the only natural source of vitamin D. Our 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 natural sunlight, they develop higher levels of this compound.

In one study, mice fed a low-calcium, low-vitamin-D diet developed symptoms of osteoporosis. In comparison, those given calcium and UV-enhanced shiitake had higher bone density.

Some also claim that mushrooms have high purine levels, which is a compound that contributes to the building blocks of DNA and RNA. This may help lower the symptoms in people with gout based on a recent study. In Japan and China, the chemicals found in shiitakes have been analyzed for medicinal properties. Extracts have been used in treating cancer, and claims have been made that they reduce cholesterol, enhance sexual power, prolong life, kill viruses, and improve circulation. 

Boost Energy and Brain Function

Shiitake mushrooms are a great source of B vitamins, which help support adrenal function and turn nutrients from food into useable energy. They have proven to help balance hormones naturally and breakthrough brain fog to maintain focus all day long, even improving cognitive performance.

Millions of Americans come up short on one or more of the B vitamins, and that causes energy slumps, unhealthy blood cell and adrenal effects, and foggy thinking. Adding shiitake mushrooms to your diet can give you the extra boost of B vitamins that you need for avoiding deficiencies.

Provide Vitamin D

As most people believe vitamin D is best obtained from the sun, shiitake mushrooms can also provide a decent amount of this essential vitamin.

Vitamin D is important for bone health as well as reducing the risk of heart disease, diabetes, autoimmune diseases, and some types of cancer. It’s vital for the absorption and metabolism of calcium and phosphorus, too.

Research indicates that getting an ample supply of vitamin D also helps regulate and support the immune system, maintain healthy body weight, maintain brain function as you age, reduce the severity of asthma symptoms, reduce the risk of developing rheumatoid arthritis in women, and reduce the risk of developing multiple sclerosis. Mushrooms, raw dairy, and eggs, as well as wild-caught salmon, are the best vitamin D-rich foods.

Promote Skin Health

When selenium is taken with vitamins A and E, it can help reduce the severity of acne and the scarring that can occur afterward. A hundred grams of shiitake mushrooms contain 5.7 milligrams of selenium, which is 8 percent of your daily value. That means shiitake mushrooms can act as a natural acne treatment.

In an open trial, 29 patients were given 0.2 milligrams of selenium and 10 milligrams of tocopheryl succinate for their acne twice daily for six to 12 weeks. After treatment, the patients noticed positive results. The zinc in shiitake mushrooms also promotes immune function and reduces the buildup of DHT to improve skin healing.

Nutrition

As far as nutrition goes, the U.S. Department of Agriculture reports that 100 grams of raw shiitake mushrooms contain about:

  • 34 calories
  • 6.8 grams carbohydrates
  • 2.2 grams protein
  • 0.5 gram fat
  • 2.5 grams fiber
  • 4 milligrams niacin (19 percent DV)
  • 1.5 milligrams pantothenic acid (15 percent DV)
  • 0.2 milligrams vitamin B6 (15 percent DV)
  • 0.2 milligrams riboflavin (13 percent DV)
  • 18 international units vitamin D (4 percent DV)
  • 0.2 milligrams manganese (12 percent DV)
  • 112 milligrams phosphorus (11 percent DV)
  • 5.7 micrograms selenium (8 percent DV)
  • 0.1 milligrams copper (7 percent DV)
  • 1 milligram zinc (7 percent DV)
  • 304 milligrams potassium (6 percent DV)
  • 20 milligrams magnesium (5 percent DV)
  • 0.4 milligrams iron (2 percent DV)

Possible side effects from raw shiitake: 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. This condition, called shiitake dermatitis, is thought to be caused by lentinan in the raw mushroom.

Short History: A great cultural export from Asia to the rest of the world

This mushroom is the second most widely cultivated mushroom in the world. It has been a popular food source in the cuisine of Asia for hundreds of years. In America, we enjoy it in Chinese and Japanese restaurants. Following recent improvements in cultivating techniques, this mushroom is quickly becoming a favorite in markets and on dining tables in the United States and Canada. 

Xi-Wang-Mu
Xi-Wang Mu, the Taoist diety called “Godmother of the West” with a Ganoderma lucidum (ling zhe) mushroom in hand. Photo by Dr. Meierhofer.
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The shiitake has a medium-sized, umbrella-shaped, tan to brown cap. The edges of the cap roll inwards. The underside and stem are white. You may find many variations when you shop for this mushroom. It has been estimated that the origin of shiitake mushrooms can be traced to the cretaceous period, over one hundred million years ago. It is found growing wild in the mountainous regions of China, Japan, Indonesia, and Taiwan. The scattering of shiitake spores has been traced using typhoon wind patterns as the mushrooms were dispersed from one to the other of these countries. It is not found wild in the United States or elsewhere.

In China, it is called dongo and shanku. When served in Chinese restaurants here it is called “the black forest mushroom.” The Japanese call the most highly prized and priced specimens donko. These have closed caps. Koshin types (spring season variety) have open caps and are less expensive.

The Chinese were the first to cultivate this mildly fragrant mushroom over six hundred years ago. The yield and quality varied from year to year until scientific techniques were developed. Japanese scientists developed a method of inserting pencil-shaped plugs of mycelial spawn grown from specially selected varieties of Lentinus edodes into holes bored in oak logs. The prepared logs carried out the work that supported the entire shiitake industry while being watched over carefully. Today it is grown in the United States as well as in Asian countries on a variety of materials containing cellulose, such as sawdust enriched with rice bran. It is sold fresh as well as dried.

Cleaning

Because shiitakes grow on wood or other coarse cellulose materials, the fresh mushrooms are very clean. Brush the caps lightly. As a rule, the stems are tough, so cut them off using a knife or scissors. The stems can be used to add flavor to the stock.

Shiitake -- Click for larger image
Source: https://www.mssf.org/cookbook/shiitake.html

References:

Mushrooms, shiitake, raw 

Shiitake Mushrooms Benefits, Nutrition, Recipes and Side Effects – Dr. Axe

Effect of shiitake (Lentinus edodes) and maitake (Grifola frondosa) mushrooms on blood pressure and plasma lipids of spontaneously hypertensive rats

Lentinus edodes promotes fat removal in hypercholesterolemic mice

Dietary calcium and vitamin D2 supplementation with enhanced Lentinula edodes improves osteoporosis-like symptoms and induces duodenal and renal active calcium transport gene expression in mice

Shiitake Mushroom Dermatitis: A Review

Eosinophilia and gastrointestinal symptoms after ingestion of shiitake mushrooms

Vitamin D and sterol composition of 10 types of mushrooms from retail suppliers in the United States

The Pharmacological Potential of Mushrooms