Serum calcitonin is a hormone secreted by thyroid follicular cells that, when elevated for some reason, increases the excretion of calcium by the kidneys and lowers blood calcium concentrations. Endemic goitre is a type of goitre. So, what should be done to prevent it when serum calcitonin levels are elevated? The following is a brief description of prevention methods: Prevention of endemic goiter disease may be effective in the prevention of this disease. 1. Iodized table salt: Add sodium iodide or potassium iodide to table salt at a concentration of 1:10,000 to 1:20,000. 2. Iodized drinking water: potassium iodide is added to drinking water, at 100,000 L of water plus 1 g of potassium iodide (i.e., 10 μg of potassium iodide per liter of water). 3.Iodine oil injection is suitable for areas with low incidence and no need for general iodization. The dose of iodine oil injection is 125mg for under 1 year old; 250mg for 1 to 5 years old; 750mg for 6 to 10 years old; 1000mg for over 10 years old and adults. 4. Eat more iodine-rich foods, such as kelp, seaweed, seaweed, sea fish and shrimp, etc. Thyroid gland lobectomy is a more reasonable and clean surgical procedure. Frozen section at the time of surgery can be followed up regularly if it is confirmed to be differentiated thyroid cancer as long as there are no enlarged lymph nodes in the neck, which will not cause medical dissemination of cancer cells. It is also possible to completely remove adenomas that are clinically thought to be solitary but are actually multiple, avoiding reoperation for adenoma recurrence.