The dangers of thyroiditis are as follows: 1. Thyroiditis affects the appearance. Clinically, thyroiditis is mainly manifested by a large neck, which seriously affects the patient's appearance and leaves a great shadow on the patient's heart. 2. Thyroiditis causes hypothyroidism. As thyroiditis progresses, it can cause slowly progressive hypothyroidism, and eventually systemic myxedema, causing functional damage to various organs. When thyroid nodules appear in thyroiditis, because the nodules are too hard, they are easily misdiagnosed as thyroid cancer and require surgical treatment. It is more likely to cause hypothyroidism and severe systemic myxedema. 3. Thyroiditis causes hyperthyroidism and exophthalmos. Patients with thyroiditis combined with hyperthyroidism may occasionally develop exophthalmos, referred to as exophthalmos. This is related to the deposition of mucopolysaccharides behind the eyeballs that cause myxedema.