There are many types of thyroid diseases, such as hyperthyroidism, hypothyroidism, etc. The causes of different diseases are different, including autoimmune factors, family genetic factors, etc. The causes of hyperthyroidism include diffuse toxic goiter, nodular toxic goiter, and autonomous high-functioning adenoma of the thyroid. 1. Hyperthyroidism: The causes of hyperthyroidism include diffuse toxic goiter, nodular toxic goiter and thyroid autonomous high-functioning adenoma, etc. Among them, diffuse toxic goiter belongs to one of the organ-specific autoimmune diseases, and there is a significant genetic predisposition, which is caused by a combination of factors. 2. Hypothyroidism: Possible causes of hypothyroidism include autoimmune damage, destruction of the thyroid gland, iodine overdose, and antithyroid drugs. Patients with thyroid disorders are advised to consult a doctor in a timely manner to determine the cause of the disease and then follow the doctor’s instructions for active treatment.