What is Hypothyroidism?

By: Swati Kumar, MD, Research Project Coordinator, Rutgers Institute for Health

Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormone for the body’s requirements. 5% of the general population is affected by Hypothyroidism, and an additional estimated 5% is undiagnosed. In over 99% of cases, hypothyroidism is caused by a failure of the thyroid gland to produce thyroid hormones (primary hypothyroidism). Primary hypothyroidism is more common in women than in men and its prevalence increases with age; incidence peaking between the ages of 30 and 50 years of age.

Environmental iodine deficiency is the most common cause of all thyroid disorders. Iodine is an essential component of thyroid hormones.  Iodine intake and hypothyroidism demonstrate a “U-shaped” relationship: decreased prevalence with mild iodine deficiency verses with severe deficiency. In the absence of iodine deficiency, the most common cause of hypothyroidism is autoimmune disease called Hashimoto’s disease. The prevalence of autoimmune thyroiditis increases in populations with high dietary iodine as well as severely iodine-deficient populations.

Some common symptoms of Hypothyroidism may include the following and could take years to develop: fatigue, constipation, weight gain, high cholesterol, depression, dry skin and hair, droopy eyelids, hoarse voice and brain fog. Diagnosis is based on clinical presentation and non-specific symptoms. Symptoms more accurately predict hypothyroidism in men than in women. In most cases, hypothyroidism is treated by replacing the amount of hormone that thyroid gland is no longer making. The most commonly used medication to treat hypothyroidism is Levothyroxine.

If left untreated Hypothyroidism can become a life-threatening condition. Symptoms could become more severe and include mental health problems, trouble breathing, heart problems, and thyroid gland enlargement. There is a high risk of developing myxedema coma without proper treatment, a serious medical condition that can be fatal.