The Startling Link Between the Thyroid Gland and Its Effects On Your Mental Well‑being

A Thyroid Disorder Could Manifest in Symptoms That Are Similar to a Mental Health Condition and Are Commonly Misdiagnosed as Such

Profile picture
Nicole Wong

Not many people are aware of the thyroid gland’s many responsibilities and the extensive impact it has on your body. An issue of over or under production of hormones by the thyroid could potentially result in debilitating symptoms that many people are not aware of. This article will explain the different functions the thyroid has and the effects that come with.

What Is Your Thyroid & What Does It Do?

Your thyroid is a gland located just underneath the larynx (Adam’s apple) and at the front of your neck. It is part of the endocrine system and secretes hormones that doctors typically refer to as T-3 (triiodothyronine), T-4 (thyroxine), and TSH (thyroid-stimulating hormone) for short. These hormones control your metabolism and affect body processes such as the rate of your heartbeat and weight gain or loss. They also regulate important functions such as the menstrual cycle, cholesterol levels, and bone density.

The Different Types of Thyroid Disorders

A thyroid disorder is typically a result of autoimmune thyroiditis, which is a chronic disease that affects the hormones produced by the thyroid gland. Your immune system mistakenly identifies the thyroid glands and its products (T-3, T-4, and TSH) as threats and generates antibodies that destroy them. Antibodies may either stimulate or inhibit thyroid gland activity. As a result, there will be either too little or too much hormone production, leading to hyperthyroidism or hypothyroidism accordingly.

1. Hyperthyroidism (overactive thyroid gland)

Hyperthyroidism occurs when there is too high a production of thyroid hormones, most commonly caused by an autoimmune condition called Graves’ disease. The increased presence of the T-3 and T-4 hormones can cause symptoms such as insomnia, accelerated heart rate, high blood pressure, anxiety, weight loss, heat sensitivity, increased frequency of bowel movements, trembling of hands, and irregular menstrual cycle.

If the general symptoms of hyperthyroidism seem familiar to you, that may be because some of them are identical or similar to the symptoms of clinical anxiety and bipolar depression. Briefly speaking, bipolar depression refers to the low periods in a bipolar disorder where one might have low levels of energy, fatigue, irritability, and even impaired concentration, all of which are present in hyperthyroidism as well. Research has also found that hyperthyroidism may result in the development of mental health issues, as an estimated 60% of people with hyperthyroidism have clinical anxiety and 69% have depression.

2. Hypothyroidism (underactive thyroid gland)

This disorder is characterized by the lack of hormones produced by the thyroid, leading to a chemical imbalance in the body. Some factors that could have caused this are:

  • Autoimmune disease – Hashimoto’s thyroiditis is a common diagnosis of hypothyroidism, where the immune system produces antibodies that attack the thyroid gland.
  • Response to hyperthyroidism treatment – The desired result when treating hyperthyroidism is to lower thyroid hormone production. However, this can result in permanently lowering or stopping production completely.
  • Medications – Medication used to treat psychiatric disorders, such as lithium, can affect hormone production in your thyroid gland.

While the symptoms of hyperthyroidism align with that of clinical anxiety and bipolar depression, hypothyroidism’s symptoms are similar to clinical depression and cognitive dysfunction. Some of these symptoms include weight gain, memory loss, cognitive impairment, and fatigue.

Apart from the effects thyroid hormone levels have on one’s mood, scientists have also recently contemplated on how autoimmune thyroiditis affects bipolar disorder. Previous research has shown that autoimmune thyroiditis could be part of the genetic vulnerability to develop bipolar, meaning that those with a genetic disposition to autoimmune thyroiditis may also be likely to develop bipolar disorder. However, recent studies are saying otherwise and there is a lack of consensus within the scientific and medical communities. Nonetheless, one thing that is widely agreed upon is that the presence of thyroid antibodies does affect the occurrence of bipolar disorder.

Other posts you may be interested in on the MyTherapy blog:

Thyroid Disorder & Mental Health Issues: A Chicken & Egg Dilemma

Having established that a thyroid disorder could cause mental health issues, one might not expect this causal relationship to be reciprocated. However, mental health disorders may also lead to thyroid disorders.

Lithium carbonate is used frequently to treat mood disorders, specifically bipolar disorder. It helps by diminishing the intensity and frequency of manic episodes while also alleviating depressive episodes. Apart from bipolar disorder, lithium is also used in treating hyperthyroidism and Graves’ disease. It hinders the production of thyroid hormones in hopes of lowering the excess hormones in the body. Ironically, due to this specific ability to reduce the presence of thyroid hormones, one of the side effects of using lithium is hypothyroidism. Hence, in a way, we can say that treating mental health can bring about thyroid gland disorders.

Another side effect of lithium is goiters. A goiter is another form of a thyroid gland disorder and is characterized by unusual growth of your thyroid gland. This growth will usually result in a visible swelling at the base of your neck and you may even feel tightness in your throat. Other symptoms can include coughing, difficulty swallowing, and difficulty breathing. A goiter forms due to changes in hormones caused by lithium and may also occur in conditions that lead to hyperthyroidism, such as Graves’ disease, and those that lead to hypothyroidism, such as Hashimoto’s disease.

Therefore, while mental health issues can develop due to a thyroid disorder, a thyroid disorder can also occur when treating a mental disorder with lithium.

Treating Thyroid Disorders and Mental Health Separately or Simultaneously

Thyroid disorders are one of the most misdiagnosed medical conditions due to the multiple similarities it shares with mental health disorders. Hence proper diagnosis is crucial in order to receive the necessary treatment.

Given that the symptoms of thyroid disorders develop gradually and are invisible to the naked eye most of the time, it is important to undergo a blood test to see if there are any abnormalities in your thyroid hormone levels (T-3, T-4, and TSH). Occasionally, your TSH result may be in the normal range, but it is usually more accurate to examine your T-3 and T-4 levels specifically. It is also helpful to track your mood swings and bodily changes such as weight loss or gain. Other observations regarding your sleep patterns and bowel movements might also prove handy in diagnosing your condition.

For those who are taking lithium on a daily basis, there’s no need to be overly concerned about the possibility of developing goiters or hypothyroidism as potential side effects. Lithium-induced thyroid problems are easily detectable and can be treated promptly with no lasting effects.

Take a look at some of the other posts on the MyTherapy blog:

Learn more about levothyroxine here:

screenshot of MyTherapy med reminder app health report

Your medication reminder & health tracker app

MyTherapy helps you stay on top of your treatment, with medication reminders, a symptom & well-being tracker, and a monthly health report you can share with your doctor.