The Thyroid's Influence
The thyroid gland, though small, plays a significant role in our physical and psychological wellbeing. It impacts heart rate, metabolism, circulation, bone health, and even our thoughts and emotions.
Watch our short film to learn about the thyroid gland's vital role, different thyroid disorders, their symptoms, and treatments.
What is the Thyroid Gland?
The thyroid gland, located in your neck, is an endocrine gland that produces two essential hormones: thyroxine (T4) and triiodothyronine (T3). These hormones are crucial for the normal functioning of all the cells in your body.
Thyroid disorders are common, particularly in women, though men, teenagers, children, and even babies can be affected. Approximately one in 20 people has a thyroid disorder, which can be temporary or permanent.
The thyroid gland is positioned just below your Adam’s apple and consists of two lobes connected by a small bridge of tissue called the isthmus. These lobes lie on either side of your windpipe.
Functions of the Thyroid Gland
The thyroid releases two hormones into the bloodstream: thyroxine (T4) and triiodothyronine (T3). T4 contains four iodine atoms, while T3 contains three. T4 is converted to T3 in the body's cells and tissues. T3 is the active form that influences the activity of all cells and tissues.
Importance of Thyroid Hormones
Thyroid hormones regulate the speed at which your body cells work. Excessive thyroid hormones cause hyperthyroidism (overactive thyroid), speeding up bodily functions, such as heart rate and intestinal activity, potentially leading to frequent bowel movements or diarrhoea. Insufficient thyroid hormones cause hypothyroidism (underactive thyroid), slowing down bodily functions, which may result in a slower heart rate and constipation.
Common Thyroid Disorders
- **Hypothyroidism (Underactive Thyroid):** Insufficient thyroxine production.
- **Hyperthyroidism (Overactive Thyroid):** Excessive thyroxine production.
Symptoms of Thyroid Disorders
- **Hypothyroidism:** Fatigue, feeling cold, weight gain, poor concentration, and depression.
- **Hyperthyroidism:** Weight loss, heat intolerance, anxiety, and sometimes sore, gritty eyes.
Symptoms can be minimal, so a blood test from your doctor is essential for a diagnosis.
Other Thyroid Disorders
- **Thyroid Eye Disease:** Often associated with Graves’ disease but can occur with hypothyroidism or normal thyroid function.
- **Nodules or Swellings:** Lumps that can impair thyroid function or cause discomfort.
- **Thyroid Cancer:** Rare but requires medical evaluation of any neck lump.
- **Postpartum Thyroiditis:** Triggered by childbirth, usually temporary but may recur with subsequent pregnancies.
How is the Thyroid Gland Controlled?
The thyroid's hormone production is regulated by the pituitary gland, located beneath the brain. The pituitary releases Thyroid-Stimulating Hormone (TSH) to activate the thyroid when hormone levels are low and stops TSH production when levels are high, maintaining balance.
Causes of Thyroid Disorders
Thyroid disorders often result from autoimmune thyroid disease, where the immune system attacks the thyroid cells. This can lead to hypothyroidism (e.g., Hashimoto’s thyroiditis) or hyperthyroidism (e.g., Graves’ disease). Thyroid problems can be hereditary.
Diagnosing Thyroid Disorders
Your doctor will assess your thyroid activity through symptoms, neck examination, and blood tests. Blood tests measure thyroid hormone levels and TSH to confirm the diagnosis. Sometimes, additional tests may be required for a comprehensive evaluation.
Our Thyroid Function Blood Test Kit can help your GP assess the function and state of your thyroid health.
More information about the thyroid and its roles in health and diseases can be found on the NHS website.
