Excess iodine may lead to weight loss, muscle weakness, and possibly goiter. Excessive iodine intake in adults may inhibit thyroxine synthesis and induce hypothyroidism, while excessive iodine supplementation in patients with iodine deficiency may also cause hyperthyroidism. Excessive iodine supplementation is harmful to the human body and may lead to toxicity, diffuse goiter, hypothyroidism and autoimmune thyroid disease, as well as thyroid tumors and may even affect intelligence. Patients with excess iodine may suffer from metabolic disorders, weight loss and muscle weakness, and long-term excess may increase the incidence of hypothyroidism. It is recommended that patients should take moderate iodine supplements, and that they should go to a regular hospital regularly for various health checks, including micronutrient tests, and adjust their diet according to the results.