For housewives, a plate of tender green wild vegetables on the dining table will whet the family's appetite. When eating out, many people also like to order a plate of wild vegetables. In the suburbs, it's often common to see many middle-aged and elderly people digging for wild vegetables in groups. Many people regard wild vegetables as "green food," believing they are pollution-free and non-toxic. However, nutrition experts point out that although wild vegetables are rich in nutrients, they need to be eaten with "full understanding," otherwise they may have adverse effects on the body. Wild vegetables are not equivalent to green food.
Associate Professor He Jiguo from the College of Food Science and Nutritional Engineering at China Agricultural University said that most of the wild vegetables available on the market and in restaurants are artificially cultivated, not grown in the wild. "Green food" refers to food that is produced in a specific way, certified by relevant national authorities, and permitted to use the green food标志 (logo), meaning it is pollution-free, harmless, safe, high-quality, and nutritious. Many cultivated wild vegetables may not necessarily meet this standard.
Some people like to pick wild vegetables in the wild, but natural wild vegetables do not mean they are non-toxic. To adapt to the harsh natural environment, wild vegetables that grow in the wild may produce certain toxic substances over the course of their long growth and reproduction to defend against external invasions. In addition, some wild vegetables have a strong ability to accumulate certain toxins, such as nitrites in toon sprouts. If the toxin content in wild vegetables is high, it can be harmful to human health, and in severe cases, it can lead to death. Don't dig wild vegetables casually in the suburbs.
Although wild vegetables in suburban fields always look lush and green, farmers actually spray pesticides to prevent pests and diseases, causing the wild vegetables growing in them to be contaminated with pesticides. Some wild vegetables grow in grasslands through which industrial wastewater flows or along roadsides. Due to contamination from wastewater, car exhaust, and other sources, their content of heavy metals such as mercury and lead, and other harmful substances is high, making it easy to get poisoned after eating them. Therefore, wild vegetables should be chosen with care; it is best not to pick them yourself and not to blindly trust the "green lies" promoted by some merchants. For office workers with dry eye disease, eating more shepherd's purse can relieve eye dryness.
Yang Qinbing, director of the Nutrition Department at China-Japan Friendship Hospital, said that shepherd's purse contains a large amount of carotene, B vitamins, and vitamin C, and its calcium and iron content are also relatively high. It has the effects of clearing heat and stopping bleeding, soothing the liver and improving vision, and promoting urination and reducing swelling.
Among common spring-planted vegetables such as spinach and bamboo shoots, all contain a certain amount of oxalic acid. The oxalic acid content in shepherd's purse is relatively low, so the calcium, iron, and other substances in it are relatively more easily absorbed by the human body. Office workers are prone to dry eye syndrome. Shepherd's purse is rich in carotene, and eating more of it can prevent dry eye disease and also alleviate the discomfort of dry eyes. Because shepherd's purse is cool in nature, people with weak spleen and stomach should not eat it, especially those with loose stools. For obese people with high blood pressure, pairing ferns with mushrooms can detoxify and lower blood pressure.
Most ferns on the market are vacuum-packed pickled products and dried goods. Associate Professor He Jiguo from the College of Food Science and Nutritional Engineering at China Agricultural University said that such packaged ferns have minimized nutritional loss, especially in vitamin C, and can be eaten more. Ferns are rich in amino acids, various vitamins, and trace elements. Some of their mineral components can dilate blood vessels and lower blood pressure, so people with high blood pressure can eat more to control their blood pressure well. Ferns can also stop diarrhea and promote urination. The crude fiber they contain can promote gastrointestinal peristalsis, has the effect of moving qi and relaxing the bowels, and can clear the intestines and detoxify. Cooking them with some mushrooms makes for the most reasonable nutritional combination. Similarly, ferns are cold in nature and people with a weak spleen and stomach should not eat too much. For beauty-conscious women, the quality volatile substances in toon sprouts can moisturize the skin.
Yang Qinbing, director of the Nutrition Department at China-Japan Friendship Hospital, said that toon sprouts are rich in vitamin C and vitamin E, and also contain high-quality protein, phosphorus, iron, etc. Their special fragrance comes from volatile aromatic organic substances such as toonin, which can strengthen the spleen and whet the appetite, and also has a detoxifying effect. These oily volatile substances can also moisturize the skin, and for women, eating more can have a beautifying effect.
However, because toon sprouts contain a relatively high amount of nitrites, attention must be paid when eating them. Data shows that every kilogram of toon sprouts contains more than 30 milligrams of nitrites, and old leaves contain up to 53.9 milligrams of nitrites per kilogram, which can easily cause nitrite poisoning. Therefore, they must be blanched in boiling water before eating to reduce the nitrite content, and simply pickling toon sprouts in salt water does not reduce the nitrite content.
In addition, it should be noted that toon sprouts are a "hair-trigger food" (a food that can trigger old illnesses or allergies). People with chronic gastrointestinal diseases, such as those with chronic enteritis or dysentery, are not suitable to eat too many toon sprouts. For people with "three highs" (high blood pressure, high blood lipids, high blood sugar), eating purslane often can protect blood vessels.
Zhao Lin, Deputy Director of the Nutrition Department of the General Hospital of the Chinese People's Liberation Army and Vice Chairman of the Trace Elements Branch of the China Association of Chinese Medicine, said that people living in the Mediterranean region have a very low incidence of heart disease because purslane is often in their diet, making it one of the world's longevity regions. This is because purslane is rich in ω-3 fatty acids, which can inhibit the production of cholesterol and glycerides in the body, reducing the likelihood of cardiovascular disease.
Generally, unsaturated fatty acids are more abundant in deep-sea fish oil and are also found in some legumes and nuts, but most vegetables contain little. Purslane also contains high levels of potassium, which can effectively protect blood vessels from harm. Middle-aged and elderly people, as well as those with "three highs," are suitable to eat more purslane.
Wang Yi, director of the Dietetic Nutrition Department at Guang'anmen Hospital of Traditional Chinese Medicine, said that purslane has a sour taste and cool nature, and has various effects such as clearing heat and promoting diuresis, detoxifying and reducing swelling, and also has a qi-supplementing effect. Chopping purslane finely and mixing it with a little lean pork to make wonton or dumpling filling, or eating it in congee, can prevent dysentery and diarrhea. For children in their growth period, eating more amaranth promotes growth.
Amaranth is a relatively common vegetable that can be bought in many supermarkets and farmers' markets.
Wang Yi, director of the Dietetic Nutrition Department at Guang'anmen Hospital of Traditional Chinese Medicine, said that amaranth is especially suitable for children in their growth period. Its carotene and niacin content are more than twice that of solanaceous vegetables; its calcium and iron content are the highest among fresh vegetables, with its iron content being twice that of spinach and its calcium content being three times that of spinach. Calcium is the main component of teeth and bones. The rich iron in amaranth can synthesize hemoglobin, has the function of blood production and oxygen transport, all of which are very helpful for the growth and development of adolescents.
The leaves and seeds of amaranth are rich in lysine, which is one of the eighteen essential amino acids for the human body and is very beneficial to human health, especially for the growth and development of adolescents, and is suitable for regular consumption.
Amaranth has a cool nature and a sweet taste, and has multiple effects such as clearing heat and improving vision, astringing and reducing swelling, and anti-inflammatory and hemostatic. It is generally suitable for most people. For some people with bleeding, hematemesis, or hematochezia, it can also be used as an adjunctive treatment. However, because amaranth is cold in nature, people with a weak spleen and stomach should eat less of it. At the same time, when eating amaranth, pay attention to avoiding eating it with other cold-natured foods, otherwise it is easy to cause symptoms such as gastrointestinal discomfort.