Hypothyroidism, also known as underactive thyroid, is a condition where the thyroid gland does not produce enough thyroid hormones to meet the body's needs. The thyroid is a small, butterfly-shaped gland located at the front of the neck that produces hormones controlling metabolism and affecting nearly every organ in the body, including heart rate, body temperature, and energy use
. When thyroid hormone levels are low, many bodily functions slow down, leading to symptoms such as fatigue, weight gain, sensitivity to cold, constipation, dry skin, muscle weakness, depression, and slowed heart rate. Symptoms often develop gradually and may be mild at first, making them easy to overlook
. Common causes of hypothyroidism include autoimmune diseases like Hashimoto's thyroiditis (where the immune system attacks the thyroid), inflammation of the thyroid (thyroiditis), surgical removal or radiation treatment of the thyroid, iodine deficiency, and certain medications. Congenital hypothyroidism (present at birth) and pituitary gland disorders can also cause the condition
. Hypothyroidism is diagnosed through blood tests measuring thyroid hormone levels (TSH and thyroxine). Treatment typically involves daily thyroid hormone replacement therapy with levothyroxine, which normalizes hormone levels and alleviates symptoms. Most people require lifelong treatment
. In summary, hypothyroidism is an endocrine disorder characterized by insufficient thyroid hormone production, leading to slowed metabolism and various symptoms, but it can be effectively managed with hormone replacement therapy
