Hyperthyroidism definitely has an effect on the body. Hyperthyroidism is caused by high concentrations of thyroid hormones in the blood. Thyroid hormones can affect the processes of material and energy metabolism, leading to increased heat production and affecting human growth and development. When the concentration of thyroid hormones is too high, it can have the following effects: i. High metabolic syndrome. Typical symptoms of hyperthyroidism are fear of heat, excessive sweating, excessive eating, easy hunger, lethargy and agitation. Second, it can cause patients’ heart rate to accelerate and produce symptoms of heart panic. Atrial fibrillation, premature ventricular beats, premature atrial beats and other arrhythmias can also occur. In severe cases, hyperthyroidism can lead to heart enlargement, heart failure and other manifestations of heart disease. Third, in hyperthyroidism, the increased oxygen consumption of the body leads to hypoxia in the liver lobules, which can easily cause liver function damage and can also lead to a decrease in white blood cells. It affects the gonadal function of men and women and leads to menstrual disorders and reduced menstrual flow in women. Fourth, hyperthyroidism can lead to hypokalemic paralysis, resulting in muscle weakness of the limbs and episodic flaccidity. V. In severe hyperthyroidism, thyroid crisis can occur under infection and other triggers. Thyroid crisis has a high mortality rate and requires active treatment.