Thyroid disease-prone coastal areas, raised questions of excessive iodine

Fatal catalyst?

In order to find a reliable doctor operated on his wife, Choi Gong-ho at the major hospitals, four inquiries, finally found a Wang Ping.

Wang is the Second Affiliated Hospital, Zhejiang University School of Medicine director of surgery doctors for many years been engaged in surgical removal of thyroid hyperplasia.

Zhejiang Province's "Iodine Love" has long attracted his attention. In recent years, he received thyroid sections where patients increased significantly. From 2005 to 2008, he personally handled the implementation of operations for more than 550 cases every year and this year was to break through the 600 cases, of which the proportion of thyroid cancer from 2005 to 10% gradually increased to 2008 23.15%.

Thyroid is the body's largest endocrine glands, located under the thyroid cartilage in the trachea close to the third and fourth cartilage rings in front. Inorganic iodine compounds in food through the gastrointestinal tract Xishouruxue cycle, the rapid enrichment of thyroid uptake. Iodide into the cells, through the role of oxidative enzymes, resulting in activity of iodine, combined with other materials to form thyroxine, and then secreted to the blood circulation.

If there is no involvement of iodine, thyroid hormone can not be a normal secretion, the body's endocrine system, reproductive system and digestive system running will be affected.

"Like a factory, iodine is a catalyst in the production process, without it, production will not carry on." Choi Gong-ho said, "but if too much catalyst, the same physiological response would interfere with the original, the result is just as bad."

In 2007, ZHANG Yong-kui in Zhejiang Province Science and Technology Department Fund's support, led a research group carried out a level of iodine nutrition in Zhoushan epidemiological investigation, the report released in April of this year. ZHANG Yong-kui In an interview with "South Du Weekly" interview, said: "We are unable to answer this survey is not iodized salt has led to the occurrence of thyroid disease, but the Zhoushan who did excessive iodine nutrition, and thyroid disease is on the rise every year."

For several months of investigation, they were urban residents in 1389 were B-ultrasonography and urine iodine test. The results showed that urban residents in Zhoushan Island median urinary iodine is 320 mg / l, 8-10-year-old children, 259 μg / l, urinary iodine value greater than the WHO designated 200 μg / l security line of people accounted for 77% of the object under investigation.

Sometimes, the hospital diagnosed 10 a day or even several dozens goiter, thyroid tumor patients and then measured the patient's urine iodine content, let Zhoushan City People's Hospital Medical surprise, almost all patients with iodine excess, while the patients changed to eat non - salt A few days later, the majority of patients with urinary iodine levels decreased significantly.

ZHANG Yong-kui can often come into contact with to make his shocking case. "Once a young female teacher, her mother just last year because of thyroid cancer received surgery to remove her also identified shortly after goiter resulted in the fine asked, her family have five individuals suffering from this diseases. "

"I treated thyroid cancer patients, the smallest is only 9 years old." Wang told reporters.

Universal side effect of iodine supplementation

Across the country, especially coastal areas, salt iodization policy has been more and more seriously questioned. Tianjin, Shenyang, Shanghai, Guangzhou, Fuzhou and other cities, every year a large number of medical survey shows dramatic increase in thyroid disease is, while the iodine excess is considered an important factor, many of which results were published in the "Chinese Journal of Endocrinology Metabolism", "Chinese Journal of Epidemiology, "and other authoritative medical journals.

Center for Disease Control in Guangdong Province in epidemiological investigation of thyroid disease for many years Zhong, many times over the past decade to conduct the investigation. As early as in 2001, he feels part of Guangdong province have high levels of urinary iodine population trends, the need to cut the amount of salt iodization in Guangdong in the 20-30 ug / g. After a few years, he also issued a number of conclusions, pointing out that in some areas related to breast milk iodine and iodized salt is too high, we should attach importance to a side effect of universal salt iodization policy.

In 2003, the Guangdong Provincial Center for Disease Control and the Gansu Provincial Center for Disease Control conducted a joint study, choose the 1996 consumption of iodized salt and Zhangjiang Wuchuan County, Huang Po Zhen iodized salt had not been implemented step Zhanjiang Xuwen County Point of Inquiry established by Thomas Chan to investigate respectively 70000 and 50000.

The results showed that iodine eight years later, Huang Po Zhen average annual incidence of hyperthyroidism has more than doubled, no iodine in Mai Mr Chan has not changed much. Zhong explained that this increased incidence is one-off nature - an increase and then declined.

With mild iodine deficiency area in the Shanghai survey also shows that: the incidence of hyperthyroidism after two years from the iodization of about 2-fold increase. The implementation of iodized salt in the prevention and treatment for many years after the old ward in the universal salt iodization, iodine hyperthyroidism did not increase, indicating the crowd has been adapted to the gradual increase in iodine intake, while the implementation of iodized salt has just taken place in prevention and treatment of new ward Iodine-induced hyperthyroidism epidemic. "

"In the iodine-deficient environment, the body will automatically adjust, such as increased thyroid volume, in order to produce enough thyroid hormones, but sudden adequate iodine intake, and the human organism has to go through a period of time to transition into a normal state. , "Zhong said.

Let Zhong unexpectedly, Xuwen in Guangdong, because of the traditional salt production, people ate mostly salt smuggling, according to CDC, Guangdong Province, the local organization's urine iodine test showed that the region with mild iodine deficiency area , the need for appropriate iodine concentration (25 ± 5) μg / g.

"At least in Guangdong, all the people go on iodine supplementation should be carried out." Zhong said, "People generally believe that coastal dwellers eat more seafood, from food to get enough iodine, but in fact not the case. Kehai per 1,000 fish about 200 micrograms of iodine a day to eat at least 750 grams in order to ensure the body's normal need to iodine, this appetite for the vast majority of people can not do. So that eating seafood is not to say iodine deficiency is not correct. "

Fifteen years of iodine supplementation

CUI Gong-hao was also a staunch supporter of salt iodization policy.

The last century, 80 years, he has worked with more than a dozen doctors in the composition of a team, rushed to the census of mountain Linan iodine deficiency disorders. Where they spent ten to twenty days, almost all the elderly population census again, thyroid disease rate of about 50% or so, most of which are caused by iodine deficiency.

China is the world's iodine was once one of the countries most seriously, there are more than 700 million population of iodine deficiency, iodine deficiency patients have been accounted for in the world group of 40%.

In 1993 the State Department hosted a "mobilization meeting on the Elimination of Iodine Deficiency Disorders", adopted a national program to combat iodine deficiency disorders outline, decided to promote universal salt iodization to eliminate iodine deficiency prevention and treatment strategies.

Officially promulgated in 1994, the State, "iodized salt to eliminate iodine deficiency hazard management regulations", the iodization of salt as a fixed policy. To 1995, except Tibet, the country implemented a consumption of iodized salt.

However, in the control of iodine deficiency disorders the same time, iodized salt may cause harm, and not paid attention to. For a long period of time, Beijing, Hebei, Shanxi, Jiangsu, Anhui, Fujian, Shandong and Henan provinces were also eight iodine mandatory iodized salt.

1 Zhejiang CDC's experts, "regulations" are actually already clearly stated: do not consume iodized salt, iodine areas, but this policy is not implemented well, many parts of the salt company in pursuit of higher profits, all Sales iodized salt. "2008 National Iodized Salt Monitoring Report" display: Many areas are still in the consumption of iodized salt iodine, in which Beijing and Fujian rate of non-iodized salt is only 25% and 22.67%.

In 2005, "China Daily" in a report Exposure: Shangqiu City, Henan Province, the Ministry of Health goalkeeper as iodine areas, requesting a salt sector "to stop the supply of iodized salt," salt company has not been ignored. In the Chinese provinces, Salt Monopoly with the goal of assessment linked to the promotion of iodized salt. Salt to implement franchise policy, Salt Company is the business and a salt management, the executive branch.

On the other hand, the departments concerned residents to monitor the level of iodine nutrition is not in place. Zhejiang iodine nutrition status survey project manager Lou Xiaoming, at present a lack of Zhejiang Province prior to 2000 CDC data. While the national level, until the National Iodine Deficiency Disorders in 2008 is just the implementation of monitoring programs.

Until 2008, Choi Gong-ho's wife found thyroid cancer, this time the national policy of universal salt iodization has been implemented for 14 years.

In the meantime, the international community about the concept of iodized salt has undergone major changes.

The last century 90's, the World Health Organization to vigorously promote the global elimination of iodine deficiency. For a long period of time, the organization believes that "Every day 1,000 micrograms of iodine intake on healthy adults is safe." In 2001, the World Health Organization for the first time iodine excess are defined that should not be encouraged daily iodine intake of more than 300 micrograms / l (urine iodine test).

Clearly, in order to CUI Gong-hao individuals are unable to reverse the salt iodization policy. After more than a year tracing, Choi Gong-ho had to admit, for excessive salt intake cause thyroid pathology he had not basis for. "This is not a person or a few experts will be able to complete the task, requiring a large nationwide survey."

"In the great popular movement against the background of iodine, iodine 500 million of adequate health of the population has been completely ignored." Cui said.

Difficult to describe the U-shaped

Despite the growing number of coastal residents suspected to point to excessive iodine intake, but there are still a lot of medical controversy.

Wang observed in clinical practice, come to the hospital diagnosis of thyroid disease patients, Taizhou, Ningbo, Wenzhou and other places are mostly in these areas are mainly distributed in coastal areas in Zhejiang Province. "From the region, it seems that showing a certain degree of relevance."

However, in Zhejiang Province, CDC provided to a reporter's investigation report was completed last year, the conclusion is the opposite. The content of the report is focused on monitoring the various counties within the province for students aged 8-10 and 18-55 year-old woman's urine iodine monitoring, the range Chun'an, Qingyuan, Anji, Tongxiang, Yuhuan, and Daishan six counties. Of which the first two is on the hill counties, the middle two are vegetable processing area, a large number of non-iodized salt, the last two counties is an island county. Survey results showed: Hill county's highest median urinary iodine, which reached 268.5 Qingyuan, while the lowest salt production areas are located in Daishan and Yuhuan, respectively, 110 and 120.

Lou Xiaoming considered that as the contrast group and the lack of comprehensive survey data, at present can not say a significant increase in the incidence of thyroid. He explained that the detection rate and morbidity are two concepts of the last century when the 90's, thyroid, primarily by palpation, and the present B-device can do more than 3 millimeters in diameter nodules can be detected. He believes that the current increase in thyroid disease, largely from the increase in detection rates.

The medical profession on the whole people before and after iodine supplementation of thyroid disease, the concern of structural change, in fact, as early as 10 years ago has begun.

Union Hospital of Fujian Medical University, Chang 闿 Jane, who conducted a 10-year investigation. They found that the universal consumption of iodized salt, so that the lower A significantly lower morbidity rate, but the increase in the prevalence of hyperthyroidism.

In Liaoning, the former president Teng Weiping, China Medical University, led research team from 1999, conducted a three-five-year "of iodine intake on thyroid diseases affect the" project.

The team selected three areas of monitoring, including an iodine deficiency region, an adequate amount of iodine super-region and an iodine excess area. The final conclusion is: iodine nutrition status is a kind of ecological environment for human survival, man-made change the ecological environment should be very cautious in iodine intake by no means the better.

Teng Weiping far-reaching implications of the study.

In March 2001 the Fourth Session of the Ninth National People's Congress, when he was deputy to the NPC, Professor Teng Weiping lead up to 9000 words, submitted a motion, proposed to amend the universal salt iodization legislation. The motion by the State attaches great importance to the timely amendment of the salt iodization relevant national standards, reduced the minimum standards for iodine content in salt. In the same year's "Prevention of iodine deficiency disease", the State proposed the "local conditions, guidance, science and iodine," the new approach.

In 2005, the state in principle, to stop the supply of iodized salt in iodine area.

"The results came out Weiping contributed to the current consensus in the medical profession an iodine intake of too much or too little can lead to thyroid disease, generally showed a U-shaped relationship, meaning that both iodine deficiency and iodine-rich LOH, leading to thyroid disease, However, the specific role of the middle of the process is not yet clear whether the iodine intake, how much is appropriate? more than what the volume is pathogenic? the various regions, different populations of individual differences is how? "Wang said.

Transfer

Held this year during the National People's Congress of Zhejiang representatives, Zhejiang Province Key Laboratory of Public Health, director of emergency response testing Lu Yi-yu again: "should pay attention to the problem of excessive salt iodine to prevent similar to the Sanlu milk powder as food safety incidents from happening again."

In Lu's proposals before the disease control departments in Hebei Province early this year put forward in the history of disease (large neck disease) counties (districts, cities), the "other regions, even if the write-off of non-iodized salt has on human health without obstacle. "

The long-term medical survey, the media attention in recent years and this year's National People's Congress proposal finally sparked concern.

Earlier this year, "National iodized salt monitoring brief" that the existence of iodine in some areas mixed region, it is recommended to carry out appropriate research and investigation the provinces to work right in line with the standard iodine areas designated cities and counties should be reported to the relevant departments as soon as possible be determined.

This year in May, the Ministry of Health to urgently convene a meeting, the final decision in Zhejiang, Fujian, Liaoning, Shanghai, four to start, "Iodine nutritional status of residents in coastal areas," survey, more than 20 professionals from the four provinces was subsequently the Ministry of Health disease Control Board meeting in Beijing for training.

In June, low-key start this project in Zhejiang. Be elected in the province a total of 13 survey points, including five coastal cities, five coastal villages, and another three counties as the comparison group, Lou Xiaoming is the one primarily responsible for the project. "At present, half of the site survey work has been completed, the census may end up in 10 months to complete."

Lou Xiaoming introduction, the survey raised eight-character principle, namely, "science iodine, and appropriate guidance," they would on this basis, the company that they would make appropriate salt iodized salt concentration of proposals.

"Salt iodization policy from an historical perspective, certainly not be withheld. But in people's living standards and health awareness-raising, you can let the residents, especially residents of coastal areas such as iodine to choose how iodine according to their own characteristics." F Xiaoming said that if the investigation supports the conclusion too much iodized salt, iodized salt in Zhejiang province is likely to face adjustment policy, "in the future in a supermarket to buy non-iodized salt may be listed in iodized salt may also be have different concentrations. "

For ongoing research, Choi Gong-ho by the medical profession has long heard of a friend, he saw the loose iodized salt policy space, but not sure what the result will be.

He is still a daily collection of newspaper reports on thyroid disease. Recently, he wrote a letter to the Zhejiang provincial local media, he wrote in the draft yard anxiously: "Do I need all the people consumed iodized salt, which is an important matter related to the national health, people of all ages to be salt, salt-an insecurity, it is more serious than melamine. "

The end of this article because the "scientific enough" was rejection.

CUI Gong-hao still often go out to buy non-iodized salt, bring proof of his wife's illness.

On one occasion, Choi Gong-ho in the Zhongshan Road to buy non-iodized salt for salt, next to a young man to buy salt, Minato came over and asked him why he bought non-iodized salt.

"My wife just had surgery for thyroid cancer," Cui Gong-ho told him.

"I just do the surgery." Lad lifted his T-shirt, from the chest through the neck, there is a shocking scars. ( "City Express" reporter Jin Lipi also contribute to this article)