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Overview
The thyroid gland, a part of the endocrine (hormone) system, plays a major role in regulating the body's metabolism.
Review Date 2/28/2022
Updated by: Debra G. Wechter, MD, FACS, General Surgery Practice Specializing in Breast Cancer, Virginia Mason Medical Center, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.