The thyroid gland is an important part of the endocrine system that plays a crucial role in regulating metabolism, growth, and development. It produces two main hormones, thyroxine (T4) and triiodothyronine (T3), which control how the body uses energy and affect many bodily functions. One of the lesser-known functions of the thyroid gland is its impact on immune function. In this article, we’ll explore the relationship between thyroid health and immune function, and why screening for thyroid disorders is essential.


The immune system is the body’s defense against infections, viruses, and other harmful invaders. It is a complex system made up of various cells, tissues, and organs that work together to keep us healthy. Thyroid health, on the other hand, refers to the proper functioning of the thyroid gland, which is located in the neck and produces hormones that regulate metabolism. While these two systems may seem unrelated, they are actually closely intertwined. According to Sri Kota Specialist Medical Centre, the prevalence of  hyperthyroidism  in Malaysia is 3.4%:  hypothyroidism is  2.1% and 3.6% for  thyroid nodules.

The Thyroid Gland

Before we dive into the relationship between thyroid health and immune function, let’s take a closer look at the thyroid gland itself. The thyroid gland is a butterfly-shaped organ located in the neck, just below Adam’s apple. It is responsible for producing two main hormones, T4 and T3, which are made from iodine and tyrosine. These hormones help regulate the body’s metabolism and play a role in many bodily functions, including heart rate, body temperature, and growth and development.

The Immune System

The immune system is a complex network of cells, tissues, and organs that work together to defend the body against harmful invaders, such as bacteria and viruses. It is made up of two main components: the innate immune system and the adaptive immune system. The innate immune system provides immediate defense against foreign invaders, while the adaptive immune system takes longer to develop and provides targeted defense against specific pathogens.

Thyroid Disorders and Immune Function

Thyroid disorders can affect immune function in several ways. For example, hypothyroidism, which occurs when the thyroid gland is underactive and produces too little thyroid hormone, can lead to decreased immune function. This is because thyroid hormones help regulate the production of white blood cells, which are an important part of the immune system.

On the other hand, hyperthyroidism, which occurs when the thyroid gland is overactive and produces too much thyroid hormone, can lead to an overactive immune response. This can cause inflammation, which can damage the body’s tissues and lead to a range of health problems.

Additionally, thyroid disorders are often associated with autoimmune disorders, such as Hashimoto’s thyroiditis and Graves’ disease. Autoimmune disorders occur when the immune system mistakenly attacks healthy cells in the body. In the case of thyroid disorders, the immune system attacks the thyroid gland, which can lead to inflammation, damage, and dysfunction.

Screening for Thyroid Disorders

Given the impact of thyroid disorders on immune function, it is essential to screen for thyroid disorders regularly. However, if you have a family history of thyroid disease, a personal history of autoimmune disorders, or are experiencing symptoms such as fatigue, weight gain or loss, hair loss, or depression, you may need to get screened more frequently.

There are several tests that can be used to screen for thyroid disorders, including blood tests to measure thyroid hormone levels and imaging tests, such as ultrasounds, to evaluate the size and shape of the thyroid gland.

Treatment for Thyroid Disorders

If you are diagnosed with a thyroid disorder, there are several treatment options available. The most common treatment for hypothyroidism is medication, such as levothyroxine, which is a synthetic form of thyroid hormone. For hyperthyroidism, there are several treatment options, including medication, radioactive iodine therapy, and surgery.

In addition to medication and other medical treatments, there are several lifestyle changes that can help manage thyroid disorders. For example, eating a healthy, balanced diet, getting regular exercise, and reducing stress can all help improve thyroid health.


The relationship between thyroid health and immune function is complex and multifaceted. Thyroid disorders can have a significant impact on immune function, and vice versa. That’s why it’s essential to screen for thyroid disorders regularly and follow a treatment plan if you are diagnosed with a thyroid disorder. By doing so, you can help maintain optimal immune function and overall health.