Auntie Zhang from Qingdao was told that she had an enlarged thyroid during a medical checkup organized by her unit. After the checkup, she went to the supermarket and bought several bags of iodized salt and seaweed and nori to supplement her iodine. When she was watching the news, she found that the media reported that the incidence of thyroid disease was on the rise in many areas of China, especially in coastal areas, and that this was related to excessive consumption of iodized salt and excessive iodine intake. Auntie Zhang went to see a doctor and learned that she had “chronic lymphocytic thyroiditis – hyperiodized goiter” and should avoid iodine and eat non-iodized salt. It seems to be an insignificant piece of news, but it is related to the dietary health of more than one billion people in China, and its ultimate problem is mainly focused on the iodine in the diet. China is one of the countries with serious iodine deficiency in general. For more than a decade, iodization of salt has greatly reduced the endemic goiter (large neck disease) and cretinism (cretinism) caused by iodine deficiency among our people. However, with the popularization of iodized salt, people are not deficient in iodine, but the diseases caused by excess iodine – chronic lymphocytic thyroiditis, some thyroid cancers, etc. – have increased. As a result, many people are concerned about whether too much iodine has been added to the salt they rely on for survival. Should the dosage be adjusted? Some people are afraid of iodine overdose and release iodine in various ways, such as exposing iodized salt to the sun and frying it in a pot. …… All the measures that were originally advertised to “protect iodine” have been reversed to “de-iodize “. As a result, many people have begun to call for a market for iodine-free salt. If you do not eat iodized salt, you are afraid of suffering from thick neck disease, but if you eat iodized salt, you are afraid of consuming too much iodine, so you are in a dilemma whether to eat or not. So, should we eat iodized salt or not? Are there other better solutions? Let me clear your doubts with the following questions. Do you know why the human body needs iodine? Iodine is one of the trace elements necessary for human growth and development, also known as “intellectual element”, mainly in the form of I2, I- and IO3-. Iodine can be combined with many elements and is not easily soluble in water but can be soluble in aqueous solutions of potassium iodide and many organic solvents. Its content in the human body is only one part in two million of body weight, and 70% to 80% is concentrated in the thyroid gland, which is an important component of thyroid hormones and an indispensable element for the development of the nervous system, while the rest is distributed in the blood. Iodine has a physiological role in promoting human energy metabolism, maintaining normal physiological functions of the pituitary gland, promoting growth and development, and normal brain development. Therefore, iodine deficiency can cause a series of diseases, and indeed, all people should start to pay attention to proper iodine supplementation. Did you know that both iodine deficiency and high iodine can be harmful to the human body? Iodine, an essential element for the human body, can cause iodine deficiency disorders when the iodine intake is too low due to the lack of iodine in the natural environment in which people live. For example, iodine deficiency in adults can lead to goiter, mental and physical retardation; iodine deficiency in children can affect the growth and development of their bones, muscles, nerves and reproductive system; iodine deficiency in pregnant women can affect the brain development of fetuses and cause miscarriage and even fetal malformation and death; iodine deficiency in infants and children can lead to “cretinism” (also called cretinism). ). In fact, people are familiar with iodine deficiency diseases, but they ignore the effects of high iodine on the human body. Iodine supplementation slightly exceeds the physiological needs of people and leads to excess iodine, which is not harmful to the majority of people, except for a few people who are sensitive to iodine, such as patients with thyroid disease, which can aggravate thyroid disease such as hyperthyroidism. In contrast, high iodine is the intake of too much iodine, which greatly exceeds the physiological requirement, i.e., 1000 micrograms per day for a long period of time, such as several months, and some people will suffer from high iodine diseases, mainly represented by hyperiodothyroidism, including hypothyroidism, hyperthyroidism, thyroid cancer, etc., caused by high iodine, which may even cause mental decline. Internationally recognized iodine research results show that the relationship between iodine intake and thyroid disorders is in a “U” shape, and both high and low iodine intake can lead to an increase in thyroid disorders. Therefore, iodine supplementation for all people should be scientific and not blindly. So who should not take iodized salt? People in non-iodine-deficient areas; patients with hyperthyroidism, because iodine supplementation will increase the synthesis of thyroid hormones and aggravate the condition; patients with chronic lymphocytic thyroiditis (Hashimoto’s disease), because iodine supplementation will aggravate the chronic inflammatory changes and aggravate the original symptoms, such as foreign body sensation in swallowing, neck pressure, breathing difficulties, hypo- or hyperthyroidism; patients with thyroid tumors, who should follow medical advice on whether to consume iodized salt or not; patients with hypothyroidism For patients with hypothyroidism (hypothyroidism), the causative factors of hypothyroidism are diverse and cannot be generalized; for patients with other thyroid diseases, they need to choose iodine salt under the guidance of doctors, taking into account their conditions and their iodine nutrition status; for pregnant and lactating women with thyroid diseases, they need to follow medical advice or take iodine supplementation for breastfeeding infants and children individually. Do you know the scientific method of iodine supplementation? In order to learn to supplement iodine scientifically, we must first grasp three “amounts”, namely, the amount of iodine in food, the amount of iodine required by the body, and the amount of urinary iodine excreted. First, let’s understand the iodine content of common foods. The highest iodine content of seafood is kelp, with dried kelp containing up to 240 mg/kg of iodine. In addition, seafood with high iodine content include seaweed, sea cucumber, clams, shellfish and sea fish. Sea fish and shellfish contain about 1 mg/kg of iodine, and sea salt contains less than 5 mg/kg of iodine. Except for seafood, the iodine content of general food is not high, and the iodine content of animal food is greater than that of plant food. Among land-based foods, eggs and milk contain slightly more iodine. Let’s look at our own iodine requirements again. Nutritionists tell us that there are quantitative standards for the daily iodine requirements of the human body: 50 micrograms per person per day for children under 4 years old, 90 micrograms per person between 4 and 14 years old, 120 micrograms per person between 14 and 18 years old, 150 micrograms per person over 18 years old, and 200 micrograms per person for pregnant and lactating women. After knowing how much iodine should be supplemented, how can I assess my iodine nutrition status? The kidneys are the main route of iodine excretion, and urinary iodine accounts for more than 80% of the total excretion. The excretion of iodine in urine can reflect the level of iodine intake, so it is easy to see your iodine nutrition status. The concept of excess iodine was first introduced by an international academic organization in 2001, and refers to urinary iodine levels greater than 300 micrograms/liter, which should be controlled between 100 and 200 micrograms/liter for normal people. Knowing the above three “amounts”, what should we do specifically? First of all, we should start with food. China stipulates that iodized salt should not contain less than 20 mg/kg of iodine, and in general, 5-10 grams of iodized salt per day, plus the iodine intake from food and drinking water, can meet the needs. Foods containing iodine can be combined with other foods, but foods with high iodine content are best not to be consumed continuously for a long time. Foods with high iodine content are suitable to be eaten lightly, such as dried seaweed boiled and softened in a pot, then taken out and eaten cold or stewed with soybeans; nori is the most nutritious soup; shellfish, clams, arks, etc. can be eaten boiled. After learning how to eat, you should pay attention to your iodine nutritional status and it is vital to learn how to monitor it. If you find that your neck is swollen, you eat a lot and you are used to being hungry, you are irritable and irritable, you get panicky easily, you have pressure pain in your thyroid gland and other symptoms related to thyroid disease, you should go to the hospital in time to prevent high iodine intake from causing thyroid disease; if you have pregnant women, nursing mothers, infants, adolescents and other people for whom iodine has an important effect, you can take them to have their urine checked regularly. If you have pregnant women, nursing mothers, infants and adolescents, you can take them to have their urine iodine levels checked regularly to ensure their iodine nutrition, but you should also remember that iodine supplementation can only prevent disease, not cure it, and you should go to a hospital to receive regular treatment if you develop symptoms. Although you know these safe and effective methods of iodine supplementation, you should not take them lightly and pay more attention to your diet. Do you know what else to pay attention to when supplementing iodine? Iodine supplementation by consuming iodized salt has the advantages of being safe, reliable, economical and easy to use. However, what are the issues that people should pay attention to when storing and consuming iodized salt? 1. How to identify fake iodized salt? First, look at the color: real iodized salt has a white appearance, while counterfeit iodized salt often has a yellowish, dark and other different colors, and is not dry enough and easily moist; second, look at the packaging: real iodized salt bags are spreading on both sides, without folding traces, while counterfeit iodized salt has obvious or inconspicuous folding traces, with obvious tooth marks; third, look at the anti-counterfeit label: the anti-counterfeit label of real iodized salt is in the same position and is very regular, while the anti-counterfeit label of counterfeit iodized salt is posted irregularly. Four, experiment: when salt is scattered on a cut potato, real iodized salt shows blue color, if there is no color reaction, it is fake iodized salt. Five, hand pinch, nose smell, mouth taste: high quality iodized salt is loose, uniform particles, no odor, pure saltiness, fake iodized salt is pinched into a mass, not easy to disperse, often mixed with industrial iodized waste residue, smells like ammonia, and tastes salty with astringency. When tasting, it is salty and astringent. 2. What should I pay attention to when consuming iodized salt? Do not buy too much iodized salt at one time, because iodine is easy to evaporate over time; do not put salt too early in stir-fry or soup, and do not add iodized salt to hot oil for frying, frying, stewing, or cooking, but put it in when the food is being cooked; store iodized salt with a lid and place it in a dry, backlit, and high temperature place; avoid taking iodized salt when taking certain drugs, such as mercury-containing drugs like vermilion, because mercury combined with iodine will produce mercury iodide. The combination of mercury and iodine will generate mercury iodide, which is not only toxic, but also corrosive, causing drug-related enteritis. Conclusion: A healthy diet starts with a little bit of life, too much or too little of any one nutrient is harmful to the human body, and only with a scientific approach to supplementation can you ensure that your body is healthy. As the old saying goes, “trouble comes from the mouth, and trouble enters through the mouth. For a healthy diet, I hope you will pay attention to “iodine”.