Mushrooms, along with cruciferous vegetables and onions are another Super Food! 
Mushrooms are not a vegetable, but rather are classified as fungi. Yes, I agree, that sounds gross, but mushrooms have amazing anti cancer and disease preventing properties.
Mushrooms have a long history dating back to the ancient Chinese, Egyptians, Greeks and Romans. The Chinese used mushrooms to treat cold and flu symptoms. The ancient Egyptians considered mushrooms a delicacy. The Greeks believed that mushrooms gave strength to their warriors. Romans only served mushrooms on special occasions, believing them to be a gift from God.
There are 14,000 different types of mushrooms, 3,000 are edible, and about 700 have known medicinal properties, and 140 are recognized as poisonous. So don’t eat mushrooms you pick in a field! Make sure they are from a reputable grocer.
Mushrooms are an excellent source of potassium, a mineral that helps lower elevated blood pressure and reduces the risk of stroke. One medium Portobello mushroom has even more potassium than a banana.
Mushrooms are a good source of selenium. Selenium is an antioxidant that works with vitamin E to protect cells from the damaging effects of free radicals and inhibiting the growth of cancerous cells. Typically we get selenium from animal protein, so mushrooms are an important food for vegetarians.
Mushrooms have been shown to be effective in preventing breast and prostate cancer. The Beta-Glucans and conjugated Linoleic Acid in mushrooms have anti-carcinogenic effects. The Beta-Glucans in mushrooms inhibit growth of cancerous cells in cases of prostate cancer.(1) Studies have shown that males who consumed twice the recommended daily intake of selenium cut their risk of prostate cancer by 65 percent. In the Baltimore study on Aging, men with the lowest blood selenium levels were 4 to 5 times more likely to have prostate cancer compared to those with the highest selenium levels. (2)
Linoleic acid is particularly helpful in suppressing effects of estrogen, the prime cause of breast cancer in post menopausal women. “Just 10 grams of mushrooms daily (about one mushroom per day) had a 64% decreased risk of breast cancer. And in women who ate 10 grams of mushrooms and drank green tea daily – an 89% decrease in risk for pre-menopausal women, and 82% for postmenopausal women.” (3)
Mushrooms care also effective for diabetics. They contain natural insulin and enzymes which help break down sugars in food. Mushrooms contain compounds that help proper functioning of liver, pancreas and the other endocrine glands, promoting formation of insulin and its proper flow through the body. (2)
Shiitake mushrooms known by the ancient Chinese and Japanese to treat colds and flu, have been shown to stimulate the immune system, help fight infection, and demonstrates anti-tumor activity. Mushrooms provide vitamin A, C and B vitamins that strengthen the body’s immune system.
Mushrooms contain natural antibiotics, as a matter of fact, penicillin is extracted from mushrooms. They also help heal ulcers and ulcerous wounds and protect them from infections.
Mushrooms are also the only vegetable to contain vitamin D in edible form. As a matter of fact, they are the second known source for edible vitamin D –after cod liver oil!
Mushrooms are also rich in calcium, iron and copper (a mineral with anti bacterial properties).
All this being said, I have taken to adding mushrooms to everything I cook!
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