Can thyroid problems cause depression?

Yes, thyroid dysfunction, especially hypothyroidism, can cause symptoms of depression. When the thyroid produces insufficient T3 and T4, it slows down bodily functions, leading to fatigue, low mood, and cognitive difficulties. In some cases, hyperthyroidism may also trigger anxiety or mood swings, but hypothyroidism is more strongly associated with depression. If you have unexplained symptoms of depression, your healthcare provider may recommend a thyroid function test (TFT) to rule out thyroid dysfunction as a potential cause. Treating the underlying thyroid disorder can often improve mood and mental well-being.