In clinical practice, thyroid hormone affects metabolism in three aspects: 1. thyroid hormone has certain influence on protein metabolism, which can promote protein synthesis and keep the body in a normal state of balance. 2. thyroid hormone has certain influence on sugar metabolism, which can increase the absorption of sugar in the gastrointestinal tract and promote glycogen xenobiotic and hepatic glycogen synthesis. 3. thyroid hormone also has an influence on human metabolism. It can affect the synthesis and decomposition of cholesterol, phosphate ester and triacylglycerol, and the overall effect is to reduce the storage of fat. Therefore, through the analysis of the above points, normal thyroid hormones are beneficial to maintain the stability of various body indicators, while abnormal thyroid hormones may have negative effects on the human body and can bring harm, and should be treated according to the specific condition.