It is best to eat salt without iodization, and eat less seafood with high iodine content such as kelp and seaweed. Others do not need to be too taboo, but you must control everything in a controlled manner. As for thyroid nodules, if B-ultrasound is considered to be benign and the nodules are small, regular B-ultrasound follow-up can be performed. If B-ultrasound is suspicious of the nodule, puncture can be performed to confirm its nature or direct surgery can be performed.