To understand Hashimoto’s disease, you need to understand the thyroid.  The thyroid is a 2-inch long butterfly-shaped gland located in front of the neck below the larynx or voice box.  It is one of the glands making up the endocrine system which produces and stores hormones releasing them into the bloodstream when needed.  Hashimoto’s disease, also known as chronic lymphocytic thyroiditis or autoimmune thyroiditis, is a disorder affecting the thyroid gland and is the most common cause of hypothyroidism in the United States.