Mushrooms: nutrition’s wonderfood
With more than 38,000 edible and toxic varieties, the mushroom is at once the most humble and the most luxurious of foods. When it comes to health, it is the shiitake and reishi mushrooms that have made a name for themselves as wonder fungi. Yet recent research has discovered that the everyday mushrooms (including the button) are just as nutritious – if not more. Welcome to the mysterious world of the mighty mushroom.
There are many reasons why mushrooms are powerful health providers. One of them is the presence of L-ergothioneine, an antioxidant that has been discovered in all varieties of mushroom but especially the common button and portabella. This free-radical fighter also protects cells’ DNA and, unlike most vitamins, survives the cooking process.
As a whole, mushrooms are some of the most nutrient-dense foods you can eat, while being virtually sodium- and fat-free and containing hardly any cholesterol. They even act to reduce bad cholesterol and promote heart health. Mushrooms also protect you from microbial infections and inhibit the growth of harmful micro-organisms.
Mushrooms are great for vegetarians and vegans as they are high in protein and full of energising and calming B vitamins. Mushrooms are also high in the trace mineral selenium. Selenium is increasingly scarce, due to nutrient depletion in the soil, but it is vital for our health because of its antioxidant, immune-supporting, anti-inflammatory and anti-cancer powers. Mushrooms also have more potassium than most other fruits and vegetables and are a vital source of energising copper and phosphorus.
Similar in shape, but darker in colour and earthier in flavour to the household button mushroom, the crimini is known to protect against cancer, notably breast cancer. One large serving provides roughly half your recommended daily allowance of selenium and riboflavin (vitamin B2), a vital ingredient for effective metabolism, energy production, a healthy nervous system and mental clarity. Crimini mushrooms are also rich in copper, other B vitamins, iron, zinc and protein. They can be cooked just like button mushrooms. For a more interesting pizza topping, try sliced crimini, Parma ham and parmesan.
For centuries the shiitake was known as the "Elixir of Life" and in its native countries Japan, China and Korea, it is a symbol of longevity. It is well respected in Traditional Chinese Medicine, where it has been used medicinally for more than 6,000 years. In the Western world, the shiitake is renowned for being anti-cancer, anti-fungal and anti-viral. It is also immune-boosting, and a strong fighter against disease and infection.
This rich, earthy and slightly meaty fungus is also a great heart protector. It lowers bad cholesterol and may lower blood pressure in people with hypertension. Then there are all its nutrients, including a good helping of B vitamins, vitamins D and C, selenium, iron and protein.
Shiitake is best prepared by lightly frying with some butter and garlic for a few minutes. The tough woody stem cannot be eaten but adds a dense and nutty flavour to stocks.
The oyster mushroom comes in many varieties. But whether it is the trumpet, the yellow, the umbel or even the common type, it is certainly the most elegant of mushrooms. It has a velvety texture, a light grey or brown colour, and a delicate yet intense flavour. The oyster is anti-viral and offers all-round support to the blood, liver and digestive system. It is also beneficial for anyone with diabetes and works to reduce high cholesterol.
While most stems of oyster mushrooms need to be chopped off, the stem of the trumpet (widely regarded as the most delicious part) gives a meaty bite to this delicate fungus. All oysters need to be cooked slightly longer than other mushrooms, as they are less tender. They work well gently sautéed, barbecued or used in stews and soups.
With its distinctive aroma and crisp texture, the maitake mushroom is known in Japan as the dance mushroom. The maitake is ideal for those who struggle with sugar imbalances or diabetes. As well as being an antioxidant and an anti-inflammatory, the maitake works to lower blood sugar levels. It also contains a wealth of potassium, which is highly beneficial for diabetics as it stimulates insulin production. This wholesome fungus also lowers bad cholesterol, promotes the formation of healthy cholesterol and evens out high blood pressure levels. Finally, it is rich in vitamins B1, B2 and D.
The Japanese love to tempura-fry their maitake mushrooms. The distinctive maitake flavour is also wonderful in stir-fries and soups.
The button mushroom has long been thought of as merely a fat-free fibre provider. But recent research has discovered that it is as nutritious as it is common. Button mushrooms are rich in phosphorus, iron, potassium, magnesium, manganese and the antioxidants L-ergothioneine and vitamin C. One serving also supplies up to 60 per cent of the recommended daily allowance of copper, which helps in the absorption of iron. The button is also high in protein and all the B vitamins, including folic acid, making it an extremely beneficial ingredient for those on a meat-free diet. Plus this everyday mushroom acts as a shield against heart disease and is thought to be anti-cancer, especially when it comes to breast and prostate cancers.
When it comes to cooking, the button mushroom is famous for being sliced in salads and sauces, but try roasting them whole with new potatoes and thyme – they’re delicious with red meat or on their own.
Another Chinese Medicine favourite, the reishi is thought to calm and nourish the emotional centre. This brown fan-shaped mushroom is a great pain reliever; it is also anti-viral, anti-bacterial and anti-inflammatory, especially in cardiovascular and respiratory systems. It follows, then, that reishi mushrooms help relieve the discomfort of illnesses such asthma and bronchitis. It is a powerful antioxidant and is packed with calcium, iron, phosphorus and vitamins C, D and B. A natural detoxifier and liver protector, the reishi also offers protection against radiation and is thought to be anti-cancer. It even lowers high blood pressure and harmful cholesterol.
Reishi mushrooms are mostly available in supplement form. But they can be bought dried or fresh from speciality stores. Their strong, intense flavour make them only enjoyable in small does. Add them to stocks and rice dishes for a dense, rich flavour.