Hypothyroidism means that you do not have enough–or even any–thyroid hormone. It is sometimes also referred to as an "underactive" or "slow" thyroid. When functioning normally, your thyroid—a small, butterfly-shaped gland in your neck—uses dietary iodine to produce thyroid hormone. The purpose of thyroid hormone is to regulate how your organs, glands, tissues, and cells use oxygen and energy. The human body needs thyroid hormone in order to survive and function. When you don’t have a working thyroid, or your thyroid is unable to produce enough hormone, the result is the condition known as hypothyroidism. There are a number of health issues and conditions that result in a thyroid that can’t produce enough—or any—thyroid hormone. (Verywell.com)
