The 4 parathyroid glands are located near or attached to the back side of the thyroid gland and produce parathyroid hormone (PTH). Parathyroid hormone regulates calcium, phosphorus, and magnesium balance within the blood and bone by maintaining a balance between the mineral levels in the blood and the bone.
Review Date 5/13/2020
Updated by: Brent Wisse, MD, board certified in Metabolism/Endocrinology, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.