What are the serious consequences of vitamin A deficiency?
Vitamin A deficiency (VAD for short) is a chronic disease with mild symptoms leading to dry eyes and severe symptoms leading to blindness and even death. When I was a kid, I would feel blurry when I read in the evening, and the old man said it was "chicken eyes", meaning the chickens were coming home to roost, so I had to give them my eyes to see the way, so the kids couldn't read at this time. In fact, this is a manifestation of night blindness caused by vitamin deficiency.VAD is a global problem, according to WHO's survey, the world has 78 countries have been recognized as having vitamin A deficiency public **** health problems, about a quarter of the world's school-age children (127 million) have vitamin A deficiency, more than 250,000 children and young people around the world every year for this blindness (1).The 2002 China Population Nutrition and Health Status Report, the Chinese population nutrition and health status of children and young people. The results of the 2002 survey on the nutritional and health status of the Chinese population show that vitamin A, iron and other micronutrient deficiencies are a common problem in both urban and rural areas in China, with a vitamin A deficiency rate of 9.3% in children aged 3 to 12 years, 3.0% in urban areas and 11.2% in rural areas; in poor areas such as the south-west of the country, the rate is as high as 50%.(2) This type of malnutrition is also known as "malnourishment". This type of malnutrition, also known as "hidden hunger", not only affects the health of people in poor areas, but also causes huge economic losses. Professor Chen Chunming of the Chinese Center for Disease Control and Prevention (CDC) estimated that the adult loss from iron deficiency in children alone was about 2.9% of the gross domestic product (GDP) in 2001; however, if measures were taken to reduce China's anemia rate by 30%, the economic benefit of increased labor productivity in adults and children in adulthood would be 455.3 billion yuan(2).The economic loss from VAD is similar.
Ways to solve VAD
Currently in the world, there are several ways to solve the problem of micronutrient deficiencies (including VAD): 1) Dietary diversity, if you have rice to eat every day, but also vegetables, fruits, and meats to eat, there is generally no problem with VAD. 2) Food fortification, in the food you must eat to add the food, the case of China's success in food fortification: one is iodized salt, which has made China almost free of iodized salt, and another one is iodized salt, which is the most popular food in the world. One is iodized salt, which has allowed China to almost completely eliminate Great Neck Disease; the other is iron-fortified soy sauce, which has also made significant progress, but because soy sauce is not a necessity for everyone, there is still a long way to go in the elimination of iron deficiencies.3) Pill supplementation, such as the large number of various vitamin tablets that are sold on the market. While these approaches can partially solve some of the problems, there are obvious limitations: 1) most of the groups in need of improvement of nutritional deficiencies are poor people, who often do not have effective means of obtaining fortified foods or ensuring dietary diversity; 2) poor groups are known to have multiple micronutrient deficiencies, not all of which can be prevented through fortification; 3) in terms of the content of the nutrients, Stability and physical properties of nutrients, the technology for fortifying various foods has not been fully developed, and the lack of knowledge about nutrient interactions complicates the technology for adding nutrients to a particular food; and 4) the cost of pill supplementation is relatively high. On the basis of these means, therefore, a more promising method of application is proposed - biofortification, a program that uses breeding and combines it with biotechnological means to increase the content of micronutrients in the main food crops, thus solving the problem of nutritional deficiencies of the poor people who eat these food crops as staple food, that is, the majority of the poor. This approach adds no additional cost and is not dependent on distribution channels.
The past life and present life of "golden rice"
Rice is the staple food of more than half of the world's population, especially the poor, and if the content of vitamin A in rice can be increased, then the problem of vitamin A deficiency among the world's poor will be solved, based on such an idea, in 1984, the Philippines Based on such a concept, at a conference held in 1984 in the Philippines, Prof. Ingo Potrykus of the Zurich Polytechnic Institute took on the burden of turning ordinary rice into vitamin A-rich rice, and after eight years of hard work, he finally launched the conceptual product, and thus he has been named one of the 100 people currently alive who have made the greatest contribution to biotechnology. In fact, ordinary rice can't synthesize vitamin A by itself, so through traditional hybridization means, you can't get high vitamin A varieties in any case, Prof. Potrykus came up with a brilliant idea, the production line of synthesizing vitamin A in the bacterium and the yellow daffodil that is, 4 genes were introduced into the rice, so that the content of vitamin A in the rice was raised from zero to a little bit more than a few micrograms per gram, and this is the first generation of the "golden rice", the first generation of the "golden rice". The first generation of "golden rice". However, this content is far from meeting the human demand for vitamin A. Theoretical estimates, if the vitamin A content of 15 micrograms / g, each person to eat four taels of rice per day, can basically meet the human body's demand for vitamin A, according to the content of each person to eat a few kilograms of rice per day, which is obviously not possible.
After the first-generation product came out, some detractors scoffed that it was just a big cake to feed everyone. Then researchers from the famous biotechnology company Syngenta took over the baton, they found a more potent gene from corn, reorganized the production line, cultivated the second generation of the "golden rice", so that the content of vitamin A increased dozens of times, each person can meet the needs of the whole day by eating less than two pounds of rice per day. The product has been made practical by the fact that it can be eaten in less than two taels of rice per person per day, which is enough to satisfy the whole day's needs.
Because of the company's involvement, Greenpeace questioned whether this was a big conspiracy by big international companies for their own ulterior commercial purposes, and that once it was promoted, the company would seek huge commercial benefits. So Syngenta and other related patents announced that they would give up all their patents related to "Golden Rice" and that "Golden Rice" would be provided to farmers in developing countries free of charge. The "Golden Rice" will be made available to farmers in developing countries free of charge, so that the "Golden Rice" can truly become a humanitarian program. The regulations include: all developing countries, including China, can use the technology free of charge; the technology can also be used in other major food crops free of charge; companies selling the crop can not increase their selling prices because of the use of the technology; farmers can also breed their own seeds to be used by the next generation.
Greenpeace's opposition:
Why does Greenpeace oppose golden rice? My personal simple understanding is that this is their work, and their important work is to oppose genetic modification. Not long ago, I heard a famous scientist say that Greenpeace was not going to oppose "Golden Rice" because they knew that it was a humanitarian project and that opposing it would result in the poor, who are the most needy and have no voice at all, enduring more disasters. I was mildly favorable to Greenpeace at the time, but their recent hype has brought my opinion back to square one. Most of the people who speak out against it here are not suffering from vitamin A deficiency. For them, the "golden rice" is optional, since the supplementation routes mentioned above are readily available to them.
What is Greenpeace arguing against? The first thing that catches the eye is that this is a "human trial," and a human trial on Chinese children at that. The truth is: this is not a safety trial at all (the safety trial of Golden Rice was completed long ago), but a trial of the conversion effect of vitamin A in humans. In fact, the vitamin A I mentioned above is not accurate, strictly speaking, it should be a source of vitamin A. This biotechnology-modified rice does not directly produce vitamin A, but rather beta-carotene, which can be converted into vitamin A in the human body. How effective is the conversion effect is, and the perfect answer is given in this joint Chinese-American trial (3), where children who eat 2-3 taels of rice per day (about one or two tael of dry rice) can meet 60% of a child's daily vitamin A requirement, the same effect as taking vitamin A pills. The authors also clearly state in the article that the trial was approved by the Chinese and American ethics committees. So it was not a sneaky trial at all.
There are also questions about why this trial was not done on American children, but on Chinese children, and mountain children at that? The answer is that the test in the United States has already been done, the above mentioned is not a "safety test", there is no safety problem, but "conversion effect" test, that is, eat in the end how the effect. Nearly half of the children in China, especially those in poorer areas, have vitamin A deficiency, and they are the ones most in need of care, whereas in the U.S. the problem is basically non-existent. More trials will be conducted in other poor areas of Asia and Africa.
Can "golden rice" solve the global problem of vitamin A deficiency? Greenpeace also questioned this and argued that the spread of Golden Rice would exacerbate the world's food security crisis. They believe that dietary diversity is a good solution to this problem, I agree that dietary diversity is a good solution, but the fact is that how many organizations or individuals in the world's poor people in addition to food, there are a variety of vegetables to eat, meat to eat it? Golden rice is not a panacea, but we need to familiarize ourselves with and respect the fact that more than 3 billion people around the world depend on rice as their staple food, and many of them eat very little else besides rice every day. Poverty is the root cause of vitamin A deficiency, and its eradication requires the ****together efforts of governments around the world. Golden Rice cannot replace the efforts being made now to address these problems, but there is no doubt that it can serve as a powerful adjunct to the process of advancing nutritional problems (especially in remote rural areas) in a lasting way.
Twenty-eight years have passed since Golden Rice was first conceptualized, since the first generation of the product was developed, since the product was perfected, and since today's difficult process of promotion has taken countless scientists and dedicated individuals their entire lives for this purpose. Such a great product should have entered the market a long time ago to save countless poor people suffering from diseases, however, due to certain organizations and individuals, either because of their own special purposes and interests, or because of the lack of corresponding knowledge, or because of the "good intentions" have been hindering the promotion and application of this product. Most of these opponents are not suffering from vitamin A deficiency, and for them "Golden Rice" is dispensable, but what about the poor? Once someone summarized the golden rice promotion of the triple obstacles, technology, patents and opponents, now technology and patents are not a problem, there is only one remaining opponents. As Professor Ingo Potrykus, one of the inventors of golden rice, said, "On the issue of golden rice, we need a more rational discussion, rather than emotional resistance."