Thyroid cancer is more common in women than in men Thyroid cancer is a cancer of the thyroid gland, and in 2008, the incidence rate of thyroid cancer in Shanghai was 5.83 per 100,000 men and 21.2 per 100,000 women. The incidence rate for women has increased more significantly than before 2008. Currently, the incidence of thyroid cancer in women has jumped to the fifth most prevalent tumor in women. The incidence rate for women is 3-4 times higher than that of men. Among thyroid cancers, papillary carcinoma is more likely to occur between the ages of 21-40. It is usually diagnosed late, as the time between onset and presentation varies from 10 months to 30 years. For this reason, women should have regular annual ultrasound thyroid examinations for early detection and treatment. Why does thyroid cancer occur? The medical community is still uncertain about the direct cause of thyroid cancer, but it is generally related to the following factors: abnormal iodine intake, genetics, and environment. Iodine and the thyroid gland are very closely related. The thyroid hormone is very important to the human body and its deficiency can cause “cretinism” and incomplete intellectual and physical development. The amount of iodine needed by the average human body is 150-200 micrograms per day. International studies on iodine show that the relationship between iodine intake and thyroid disease is U-shaped, with both high and low iodine intake leading to an increase in thyroid disease. When there is an excess of iodine, the thyroid gland regulates itself to be insensitive to iodine and the excess iodine is excreted in the urine. After a period of time, even if a normal amount of iodine is consumed, the thyroid gland cannot absorb iodine and cannot synthesize thyroid hormones. The thyroid gland then regulates itself to a “hypersensitive” state and becomes hyperfunctional, and after a long period of excitement, the thyroid gland becomes overstretched and swollen. Likewise, when the amount of iodine is not enough, the thyroid gland becomes “hypersensitive” and works very hard, which can cause problems over time. Ultrasound screening is the first choice for thyroid cancer. Since the thyroid gland is located under the skin of the neck, it is easy to be detected and palpable once enlarged. Although it has been recognized and deepened for thousands of years in human history, in the past, the diagnosis of thyroid disease relied only on the touch of the doctor’s hand. The chances of finding and detecting thyroid lesions were not high. It was not until the advent of ultrasound and color ultrasound technology in the late 1980s that the diagnosis of thyroid disease was revolutionized. Nodules under 1 cm that were previously untouchable and changes in blood flow around the thyroid gland are clearly visible. In particular, the high-frequency ultrasound technology of the thyroid gland, which has been adopted in recent years, is able to clearly display not only the anatomical structure, hemodynamics, and microcirculatory perfusion of the thyroid gland, but also to detect tiny nodules of 2-3 mm, as well as to accurately distinguish between glial retention and substantial masses of the thyroid gland, and to determine whether necrosis has occurred in substantial masses, among other valuable information. Iodized salt is a merit or a demerit for the thyroid gland In fact, the intake of iodine should be done in two ways, depending on the individual and a reasonable intake. Normal people should also avoid the two extremes of not consuming iodine at all and consuming large amounts of iodine. What does iodine do to the body? Iodine is the raw material for thyroxine. Lack of iodine can cause low thyroxine and turn into hypothyroidism. Patients with hypothyroidism can cause low basal metabolism in the human body, making the body feel weak and cold, and in severe cases, mucinous edema can occur, and fetuses, infants and adolescents can produce brain development retardation. Therefore, iodine is an indispensable nutrient for the human body. However, excessive iodine intake does increase the risk of hyperthyroidism. Therefore, iodine should neither be consumed too little nor too much. It has been reported in the United States that the western part of the United States was originally iodine deficient in the last century, and at that time, 20% of thyroid cancer in the United States was hypofractionated cancer, which is one of the most malignant tumors in human beings, and almost no one could live longer than one year after being detected. After the 1930s, when iodine was added to salt in the United States, the incidence of undifferentiated thyroid cancer gradually decreased to 1%, while the incidence of papillary thyroid cancer increased, but we all know that most papillary cancers can be cured with timely and standardized treatment. In this case, we can see that iodine has both merits and demerits, and we cannot simply say that it is good or bad. Whether the amount of iodine is related to the development of thyroid tumors needs to be further investigated. Therefore, it is not a bad thing to add iodine to salt, and whether or not to choose iodized salt should be entirely based on oneself. It is recommended that for people who are already suffering from hyperthyroidism, they should eat non-iodized salt, while for normal people who do not have hyperthyroidism, they should not reject iodized salt. Theoretically, to see if one’s intake of iodine is more or less, one should check the urinary iodine. Generally speaking a person’s intake of 150 micrograms of iodine a day is enough, and more than 300 micrograms is too much. For the people, whether to choose iodized salt or not, you can refer to two of these situations to choose 1. people in coastal areas, who usually consume more iodine-rich foods such as seafood and nori, can choose non-iodized salt; 2. people with hyperthyroidism should choose non-iodized salt.