"Iodine is an essential trace element in biology, which mostly exists in seawater, rocks or sediments. Although Taiwan Province Province is an island surrounded by the sea, China people's eating habits are different from those of Japanese and Koreans in coastal countries. They often eat foods with high iodine content such as seaweed and kelp. In addition, the geographical conditions and soil in Taiwan Province are not conducive to the retention of iodine, so iodine deficiency in the country has always been a part of public health policy. 」

Is there no shortage of iodine on the island? Break the myth of iodine

On May 2, 20041,the National Health Bureau released the news of mild iodine deficiency in China. This conclusion is based on the results of a 6-year urine iodine survey in China. Many people are puzzled by iodine deficiency in China. Arguably, there should be no shortage of iodine on the island, and iodized salt is used in Taiwan Province Province. If there are no symptoms of goiter, iodine is enough. However, these are just long-standing misconceptions and inferences.

In fact, there are few seaweeds along the coast of Taiwan Province Province, and the rivers fluctuate, which is not conducive to the retention of iodine in the soil. Since the Japanese occupation, goiter has been prevalent in Taiwan Province province, even pigs are no exception. So the idea that there is no shortage of iodine on the island is completely wrong.

Cyclic journey of iodine

(Figure 1) Biogeochemical Cycle of Iodine in Nature. The topography and coastal environment in Taiwan Province Province are not conducive to the retention of iodine in water and soil. (Figure/Professor Xiao Ningxin is authorized to use in this article. Please contact the author if you need a separate quotation. Like carbon or nitrogen, iodine has a "biogeochemical cycle" between the biological world and the abiotic world (figure 1). Marine plants such as microalgae and coastal macroalgae are the largest iodine banks, and their tissues are particularly rich in iodine. Iodine released from seawater and plants reacts with photolysis and ozone to generate various gaseous iodine, which enters the atmosphere and then undergoes various chemical reactions to form relatively stable inorganic molecules and tiny aerosol particles. These particles become larger and larger, and settle on the ground and fresh water rivers with rain or dust particles. Iodine in soil and water can be used by animals and plants and enter the human food chain. However, iodine ions and iodate ions in soil are easily lost with water erosion.