It is estimated that there are nearly 1,40,000 species of mushrooms. Among the unexplored and unexamined mushrooms, if the proportion of useful mushrooms is even 5 per cent, it suggests that nearly 7,000 undiscovered species would provide benefits to mankind.
Nutritionally they are very low in calories, carbohydrates, virtually fat free, good source of dietary fibre, modest protein and rich in minerals, particularly potassium (which helps in controlling blood pressure), selenium (a powerful antioxidant) and plant chemicals, which may boost immune function. They also provide some amount of folate, zinc and Vitamin C, B vitamins including riboflavin, thiamine, niacin and B6. They are among the best plant-based sources of niacin. Vitamin A and D are rarely found but certain species contain detectable amount of Vitamin D when exposed to UV light.
Half cup (78 g) cooked mushrooms provide about 20 calories, 1.7 g proteins, 1.6 gm carbohydrates, 278 mg potassium, and 3.5 mg niacin.
Portobello and white mushrooms are good sources of Selenium, which may help prevent prostate cancer as it is known to work with Vitamin E to clean up the free radicals that damage cells.
Mushrooms are also very high in glutamic acid, an amino acid that seems to be instrumental in fighting infections.
Ancient cultures recognised that mushrooms could have valuable health benefits. The varieties that show potential medicinal and functional properties include Shiitake, Ganoderma, Lentinus, Auricularia, Hericium, Grifola, Flammulina, Pleurotus, and Tremella.
Historically known benefits of mushrooms include immune-modulatory, hepato-protective, antinoceceptive (pain relieving), cardio-protective, anti-diabetic, anti-oxidant, anti-cancer, anti-viral and anti-infective properties. They are, in fact, a perfect example of a functional food or a super-food and several scientific studies are demonstrating their benefits to human health.
While mushrooms are a long-time staple of Asian cuisines, most of the early scientific studies on the health benefits of mushrooms have been done in Japan and China.
Research in Japan indicates that Shiitake mushrooms contain lentinan, a phytochemical and a cancer-fighting substance. Lentinan may also help boost immune activity. Eritadenine, another chemical present in Shiitake mushrooms helps lower cholesterol by promoting cholesterol excretion. Other compounds in Shiitake mushrooms are being further studied.
Another variety, Ganoderma, has been utilised for centuries in East Asia, particularly Japan and China, for general health, longevity, prevention or treatment of various diseases and reducing the likelihood of cancer. Both root and body of Ganoderma have distinct benefits. The primary bioactive compounds are polysaccharides and organic germanium. Scientific evidence supports that Ganoderma extract and its bioactive compounds may have a potential inhibitory effect on cancer, particularly prostate and breast cancers.
Low in calories, mushrooms can be generously included as a part of low-calorie, low-fat diets. They combine well with vegetables and grains in stir-fry, stew, soups, casseroles, sautéed dishes and barbecues. They not only lend a meaty texture to food but enhance flavours owing to their high concentration of glutamic acid -- the naturally occurring form of monosodium glutamate (MSG).
With the discovery of such a wide array of benefits, mushrooms may not only be adding flavour and texture to your food, but can prove to be truly a food which could be your medicine.
Although it is true that mushrooms contain toxins, the good news is that cooking reduces these substances. The common white mushrooms contain traces of the carcinogen agaritine and hydrazines, which can be eliminated and destroyed by cooking.
There is no completely foolproof way of distinguishing safe and unsafe wild mushrooms. Many wild varieties are poisonous. Among poisonous varieties, only a small number may cause serious problem. The severity of mushroom poisoning varies with the amount and type of mushrooms eaten as well as with the season. As a rule of thumb, if symptoms appear within two hours after eating mushrooms, the illness probably will not be severe. If symptoms develop more than 2 hours after eating the mushrooms, emergency treatment may be required. Recovery in most mushroom poisonings is excellent. In general, avoid eating unknown wild varieties - stick to known varieties commonly sold at food stores.
Source: Ishi Khosla/Indian Express