There are many reasons for solid thyroid nodules, commonly found in the following points: First, the lack of thyroxine raw materials, the most common is the lack of iodine in the environment, such as endemic goiter, etc., which can be improved by eating iodized salt and appropriate intake of iodine-rich foods, such as kelp, seafood and other foods. Secondly, the increase in thyroid demand, which is common in adolescent, pregnant or menopausal women, can be improved by taking oral thyroxine tablets, eugenol and so on. Third, thyroxine synthesis and secretion dysfunction, for example, suffering from thyrotoxicosis, diffuse goiter and so on. If nodular goiter occurs, it is necessary to further go to the hospital to improve the relevant examination to check whether it is caused by lack or malignant changes and other conditions.