A thyroid is a butterfly-shaped gland in the middle of the neck in front of the trachea. The thyroid produces thyroid hormones that control the metabolism and influence every organ, tissue and cell in the body. They also control heart rate, body weight, temperature, energy level, muscle strength and menstrual regularity. Thyroid disease is a condition that affects the amount of thyroid hormones being produced and the main conditions of thyroid disease are hypothyroidism and hyperthyroidism.
Attribution: Straight Talk Foundation