Diet <1> Avoid eating: greasy (such as rooster, goose, pork, beef and mutton, carp, shrimp, crab, etc.), spicy (such as raw onion, ginger, garlic, chili, etc.), fried food. <2>Ban smoking and alcohol. <3> Eat more: seaweed, seaweed and fresh vegetables and fruits. Second, keep a happy mood. Psychologists believe that the occurrence of tumor has a great connection with people’s mood, and long-term depression and sadness are very easy to induce cancer, therefore, people should not be troubled by bad mood, learn to ventilate and let themselves have a good mood. Actively treat benign thyroid tumor. Nodular goiter: the incidence rate of thyroid cancer is 5-10%. Thyroid adenoma: the cancer rate of thyroid adenoma is as high as 10%-20%. Chronic lymphocytic thyroiditis: the incidence of thyroid cancer is 4.3-24%. ④ Hyperthyroidism: the incidence of thyroid cancer in hyperthyroidism surgery is 2.5-9.6%. When hyperthyroidism is combined with multiple thyroid nodules, thyroid cancer should be alerted. Iodine and thyroid cancer. Iodine is an essential trace element, iodine deficiency can lead to reduced synthesis and secretion of thyroid hormones and increased levels of thyroid stimulating hormone (TSH), and long-term chronic stimulation of TSH can lead to hyperplasia and hypertrophy of thyroid follicles, and even the formation of nodules or cancerous lesions. A high iodine diet likewise alters the structure and function of the thyroid gland and may increase the incidence of papillary thyroid cancer. The correct practice is to consume iodized salt or moderate intake of iodine-rich foods such as seaweed and seaweed to ensure the physiological needs, over and under are not desirable. Radiation and thyroid cancer. The history of head and neck radiation exposure or radioactive dust exposure during childhood, and the history of systemic radiation therapy have been clearly recognized as the risk factors of thyroid cancer. In the past, it was believed that irradiation treatment for head and neck malignant tumors such as lymphoma increased the incidence of thyroid cancer. It is worth noting that recent studies have confirmed that children undergoing dental surface tomography for various dental conditions increase the incidence of thyroid cancer nearly twofold. In addition, children undergoing CT examinations that expose the thyroid gland to radiation, such as CT of the chest, head, or sinuses, are at increased risk for thyroid cancer. The younger the patient, the higher the risk of thyroid cancer after receiving head and neck irradiation. Therefore, we recommend that children with a history of head and neck irradiation should undergo long-term follow-up with thyroid ultrasound; on the other hand, physicians should also accurately assess the necessity of radiological examinations or treatments in order to minimize unnecessary irradiation. Sixth, family genetic factors and thyroid cancer. A small number of DTC has some family genetic predisposition. family history of DTC, medullary thyroid carcinoma or multiple endocrine adenomatosis type 2 (MEN2), familial polyposis, etc. or family history are also risk factors for thyroid cancer. In addition, some familial syndromes or hereditary diseases such as Cowden syndrome, Werner syndrome and Gardner syndrome also have a tendency to be combined with DTC. Currently, studies have confirmed that metabolic disorders caused by obesity will increase the risk of thyroid cancer. Therefore, improving dietary structure, increasing the intake of fresh vegetables and fruits, as well as exercising appropriately, controlling body weight and reducing obesity have certain positive effects on the prevention of thyroid cancer. Finally, we especially advocate prevention as the mainstay for tumors in any part of the body. Above we mainly talk about primary prevention, that is, prevention against the cause of the disease. Secondary prevention refers to early detection and early diagnosis. Regular health checkups are of great significance to the early detection of diseases. For the prevention of thyroid cancer, we recommend regular ultrasound examination of the neck and measurement of thyroid hormone and TSH levels, especially for people with risk factors for thyroid cancer. If thyroid nodules are detected, the TI-RADS classification results should be used to determine the disposition plan, and patients with benign nodules should be followed up for a long period of time in order to detect any changes in their condition in a timely manner. In conclusion, thyroid cancer can be prevented and cured, we should pay attention to it, but do not be overly nervous. As long as patients with thyroid cancer face it positively and cooperate with doctors’ individualized treatment plan, most of them can obtain long-term survival.