Recently, WeChat circles frantically forwarded a message about iodized salt, saying that the intensified use of [potassium iodate] in iodized salt in China was an American conspiracy, and also mentioned a top secret [I3050 Project to Destroy China].
I can’t help but wonder, how did you know about the top secret plan? What kind of top secret plan will have such a straightforward name? Think of Manhattan Project, Apollo Project, Operation Overlord?
Funny, please also be serious.
What are potassium iodide and potassium iodate?
1. Potassium iodide
Potassium iodide is very soluble and can be sprayed on dry salt after atomization. However, it is not very stable. Salt can be affected with damp or exposed to humid air, light, heat, acidic environment, impurities and other factors can make it ineffective, such as water turning into water vapor and flying away.
Potassium iodide is very unstable if it is strengthened by crude salt with low purity. If the woven bag containing salt is affected with damp, potassium iodide will dissolve out and adsorb on the bag, eventually leading to iodine loss.
In order to avoid iodine loss as much as possible, it is necessary to improve the purity of salt and keep it dry as much as possible. Stabilizers and desiccants, such as sodium thiosulfate (soda), calcium hydroxide (hydrated lime), magnesium carbonate, calcium carbonate and other compounds, need to be added.
Generally speaking, potassium iodide is used to increase iodine in salt, which requires a series of auxiliary conditions.
2. Potassium iodate
In view of a series of shortcomings of potassium iodide, the advantages of the upgraded version of potassium iodate are obvious.
- The requirement for salt purity is not high, the requirement for environment is not high, and potassium iodide is not needed compared with stabilizer and desiccant. It is not easy to run to the packaging bag and lose potassium iodate. Although it is more expensive, But the overall price is lower than that of potassium iodide. Although the price of potassium iodide is cheaper than that of potassium iodate, However, if the factor of iodine loss is taken into account, the comprehensive cost of using potassium iodide (harsh storage environment, demand for stabilizers and desiccants) may be higher. The amount of iodine supplement is easier to grasp. Due to the instability of potassium iodide, the iodine content in salt is easy to be uneven, while potassium iodate is stable and easier to control.
Potassium iodate is ten times more toxic than potassium iodide?
It is widely reported on the Internet that [potassium iodate is 10 times more toxic than potassium iodide], and the reason comes from toxicological parameter [lethal dose 50]. This is also quite funny, to know that the lethal dose 50 of salt is smaller than melamine, what does what mean?
The smaller the LD50, the less the amount of death is needed, so the same amount of salt and melamine are more likely to die from eating salt.
Although salt seems to be very safe, it should also be used at a safe dose. No matter how safe salt is, if you eat too much at one go, you will have to die of salt.
Therefore, the crux of the problem lies in whether it is safe under the actual usage, rather than a simple comparison of toxicological parameters.
For example, the safe amount of potassium iodide is 100 and the safe amount of potassium iodate is 10, but the actual usage amount is only 1. Isn’t that all safe?
Excessive iodine supplementation or iodine deficiency are harmful.
Excessive and too little iodine will increase the risk of hyperthyroidism and hypothyroidism, but there is still no relevant evidence for the relationship between iodine excess and thyroid cancer.
No matter potassium iodide or potassium iodate is used, the amount of iodine supplement needs to be determined according to the needs of human body.
This national [one size fits all] iodine supplement policy does have its drawbacks, but it is not advisable to cancel iodine supplement [one size fits all].
1. The iodine content in salt has been lowered.
On March 15, 2012, China implemented a new standard of < < salt iodized salt content > >. According to previous investigations, the iodine content in salt has been lowered, and all localities can determine the iodine content in iodized salt according to the actual situation of the province, so that the iodine nutrition of the population is at an appropriate level.
But even so, the national iodine supplement still brings an obvious drawback:
This makes it difficult to buy salt without iodization on the market!
For people suffering from thyroid diseases, many need to eat salt without iodization, which has caused them great troubles in their lives.
2. It may have to be raised in the future.
Ten years ago, the salt intake of Chinese residents was about 12g per day, but through ten years of health education, it has dropped significantly.
If it continues to drop to about 6 grams of the recommended dietary amount, it means that the iodine intake through salt will also be reduced by half. At that time, the amount of iodized salt may need to be increased.
Do you eat iodized salt or not?
In 1991, The prevalence of iodine deficiency disorders will be reduced within 10 years. Since the official implementation of the salt iodization policy in 1995, By 2000, China had eliminated iodine deficiency disorders at the overall level, and this remarkable effect has been fully affirmed by the international community. Taking the prevalence rate of macroneck disease among children aged 8-10 as an example, China has carried out five large-scale national surveillance successively from 1995 to 2005, and the following chart gives annotations.
It is important to stick to the salt iodization strategy, In 2006, 34 villages in 11 townships in Xinjiang saw new cretinism patients, with a total of 76 patients under the age of 15. The direct reason is that the coverage rate of iodized salt has dropped sharply, which also proves the effectiveness of salt iodization from another side. Even some studies have found that after iodine supplement, our children’s IQ has been improved, which makes all kinds of brain tonic holy products feel comparable.
Although China has achieved the stage goal of eliminating iodine deficiency disorders, the harm of iodine deficiency is caused by iodine deficiency in the natural environment, and the iodine deficiency in the natural environment cannot be changed.
For most people, if iodized salt is not eaten, people will be harmed by iodine deficiency due to iodine deficiency.