There is a certain degree of severity, but the exact severity needs to be determined by the extent of the condition. The thyroid gland is one of the most important endocrine organs in the body. When thyroid gland disease occurs, it usually affects the metabolic system, the nervous system, the cardiovascular system, and in severe cases, it can even be life-threatening. When you have a thyroid disease, you need to have your thyroid function checked regularly. The majority of thyroid disorders are benign and generally have little effect on the body, and symptoms can be controlled or relieved to some extent through treatment. Hypothyroidism can affect the nervous system, endocrine system, digestive system, etc. It can sometimes lead to impotence and premature ejaculation in men, and may cause infertility in women. Hyperthyroidism can cause tachycardia and arrhythmias in patients, and in severe cases cause disruption of the menstrual cycle in women, leading to infertility. Diffuse goiter can also sometimes compress organs and cause difficulty in breathing and swallowing, which may require surgery. Thyroid disorders need to be treated promptly to avoid adverse health effects.