Selenium is the most expensive thing. Where is it?
Selenium is a chemical element, which is recognized as an essential trace element by the World Health Organization and the International Nutrition Organization in 1972. 1988, China Nutrition Society listed selenium as one of the essential daily nutritional elements for human body. It is found that selenium is an important antioxidant in human body, which can eliminate harmful free radicals, prevent vascular aging and prevent cardiovascular and cerebrovascular diseases. In addition, selenium can also improve immune function and increase body resistance. Appropriate selenium supplementation in tumor patients can increase the body's tolerance to chemotherapy and radiotherapy. As a result, the concept of "selenium is a good thing" has gradually been recognized by the public, and selenium-enriched foods have also appeared.
The so-called "selenium-enriched foods" can be divided into three categories: one is selenium-enriched foods, that is, selenium-enriched compounds are added to foods, such as selenium-enriched soy sauce and selenium-enriched biscuits; Second, natural selenium-enriched foods, that is, natural selenium-enriched foods developed and produced by using abundant selenium resources in selenium-enriched areas, such as Hainan selenium-enriched sweet potato and Hubei Enshi selenium-enriched tea; The third is artificially transformed selenium-enriched products, that is, inorganic selenium is transformed into organic selenium by microorganisms or animals and plants to improve the bioavailability of selenium, such as selenium-enriched eggs and selenium-enriched milk produced by livestock eating selenium-containing feed.
At present, Chengmai, Ding 'an and other places in Hainan have pioneered the way of "selenium" and vigorously developed selenium-enriched characteristic agriculture such as selenium-enriched sweet potatoes and selenium-enriched rice. "Different crops have different selenium contents. In addition to the selenium content in the soil, it will also increase the selenium content by supplementing nutrients. " Zheng Daojun, deputy director of the Institute of Tropical Horticulture, Hainan Academy of Agricultural Sciences, introduced.
With people's strong demand for various selenium-enriched foods, some merchants have also promoted them to the extreme, shouting "selenium-enriched" as a selling point, and the "value" of selenium-enriched foods has gradually increased. "The selenium-enriched rice I bought in the supermarket is almost twice as expensive as ordinary rice. I have also bought selenium-enriched sweet potatoes, and the price gap is not very big. Sometimes you can get some discounts when doing activities. " Haikou citizen Ms. Yang said.
"Selenium" supplements, the more the better?
"I read a lot of information about selenium supplementation on the Internet, so I bought some more to eat." In a fruit and vegetable group in Haikou, Ms. Wang is a frequent visitor to selenium-enriched sweet potatoes and selenium-enriched lychees. She holds the idea that "eating more selenium-enriched foods is beneficial" and always wants to join the group when she meets new products.
Is it really beneficial to eat more selenium-enriched foods? Actually, it's not. Selenium supplementation should also be appropriate.
Xu Chao, director of the clinical nutrition department of Haikou People's Hospital, said that Keshan disease is a serious heart disease caused by selenium deficiency. It appeared in Heilongjiang at 1935, but it was basically eliminated at the end of last century. With the gradual improvement of nutritional supplements, serious selenium deficiency is rare at present. If excessive selenium is added, once it exceeds the limit, it will easily lead to selenium poisoning.
"Don't think that some kind of selenium-enriched food is good. Just eat it three times a day. It's unnecessary." Xu Chao said that although selenium has a certain antioxidant effect on the human body, it cannot be blindly supplemented. Reasonable intake is the reasonable way to supplement selenium.
In addition to the misunderstanding of "supplementing more", many consumers are easily misled by the selling point that "selenium can fight cancer". In fact, selenium has antioxidant activity, and it shows inhibitory effect on some cancer cells in animal experiments, but "containing ingredients that can kill cancer cells" does not mean "eating it can resist cancer". "Selenium has a certain effect, but there are many pathogenic factors of tumor diseases, which cannot be solved by eating selenium-enriched foods alone." Xu Chao said.
How to scientifically supplement selenium?
According to the national health industry standard, the average daily selenium requirement of adults is 50 micrograms, the maximum intake is 400 micrograms, and the recommended intake is 60 micrograms. Although the problem of serious selenium deficiency has rarely appeared at present, there is still a sub-health state.
For some teenagers and children, partial eclipse and picky eaters may lead to selenium deficiency, which may lead to decreased immunity. For some people suffering from malignant diseases, such as cancer patients, due to radiotherapy, chemotherapy and other reasons, appetite decreased and diet structure changed, resulting in selenium deficiency.
In view of the above situation, Xu Chao suggested giving priority to food supplement, such as marine food, visceral food, cereals and potatoes, which are rich in selenium, while vegetables and fruits do not contain selenium. In addition to the above two groups of people, as long as the average adult maintains good eating habits and balanced nutrition, the elements needed by the body can also be met to a certain extent, and there is no need to deliberately supplement selenium.
Facing the complicated selenium-enriched foods on the market today, how to identify them is also a key. Xu Chao said that it is difficult to distinguish it from the appearance alone, and it can be bought and eaten by identifying a unified national geographical indication trademark. But in any case, balanced nutrition is the key to maintaining good health. Selenium is the most important thing in the real sense, that is, not too much selenium should be supplemented to achieve the content needed by the human body, and selenium should be supplemented scientifically and reasonably.