Your Thyroid and Your Mental Health

At the Hayakawa Mental Health Clinic Issha in Nagoya, we often request that our patients undergo a blood test to see if their thyroid is functioning correctly.

The thyroid is a small gland in your neck, just in front of your throat. The gland produces hormones that are essential for converting food into energy and supporting growth. When you have an under-active thyroid, it can affect lower hormone production, disrupting your brain’s chemical signaling. If the thyroid produces too many or too few hormones, it can cause mood changes and symptoms, which may include:

• Behavioral changes
• Depression
• Anxiety
• Difficulty learning new things
• Memory problems
• Speaking difficulties

(For More info see:

About Major Depressive Disorder and your immune system:

The most common organ affected by autoimmunity is the thyroid, with up to 5% of the general population suffering from autoimmune thyroid diseases.

Newly emerging data indicate that the immune system may be a potential factor contributing to the development of depression. One of the first studies to show the connection between autoimmune thyroid disorders and depression was conducted in 1998. The results showed a higher prevalence of Major Depressive Disorder (MDD) among patients with Hashimoto’s Thyroiditis (a condition in which your immune system attacks your thyroid.)The findings of another study indicated that hypothyroidism might increase the predisposition to depression.

(See: The link between thyroid autoimmunity, depression and bipolar disorder at

So what is the takeaway? As we often say here at our clinic: Mental health is part of physical health. Your brain is part of your body, and seeking treatment for mental health issues should be considered just as normal as treatment for any other aspect of your body. While multiple factors can cause depression, it is also important to get your blood tested, especially if you are being treated with pharmacological medicine for symptoms of depression and anxiety.