Sometimes depression results from an underactive thyroid, from the Harvard Mental Health Letter
Nearly 10 million Americans suffer from hypothyroidism, a condition in which the thyroid gland is underactive. In some people, hypothyroidism may be mistaken for depression. These individuals may be prescribed an antidepressant, rather than the thyroid medication that they really need.
The July 2011 issue of the Harvard Mental Health Letter explains how to distinguish hypothyroidism from depression and describes the treatment options for mood problems caused by an underactive thyroid.
The thyroid gland is a small butterfly-shaped structure in the neck. Although it weighs less than an ounce, the thyroid exerts a powerful influence throughout the body. It does so by secreting hormones that control how fast and efficiently cells convert nutrients into energy (metabolism). By regulating metabolism, the thyroid indirectly affects every cell, tissue, and organ in the body — including the brain.