Thyroid Gland

What is Thyroid?

The thyroid gland is a ductless endocrine gland situated in the anterior/front portion of the neck. It roughly resembles the shape of a butterfly. It is also one of the largest endocrine glands, weighing an average of 25 – 30 g. This gland has two lobes on either side of the trachea, with each lobe measuring 4 – 6 cm in length and 1.3 – 1.8 cm in width.

Thyroid gland

The primary function of the thyroid gland is to secrete two hormones, namely, Triiodothyronine (T3) hormone and the Thyroxine hormone (T4). Both T3 and T4 hormones play a very important role and affect almost every tissue in the body.

Thyroid Problems

The thyroid gland is susceptible to many disorders and diseases. These problems might be due to the excess secretion of hormones, unusual growth of the gland, malignant lumps etc. Also, scientists have theorized a relationship between stress and thyroid health. I.e., stress may actually aggravate the underlying thyroid condition. Some of the common thyroid problems are:

Goitres

It is an excessive enlargement of the thyroid gland often obstructing the oesophagus or other organs in the neck and chest by causing difficulty to eat and breathe.

Thyroid problems and diseases

Thyroid cancer

It is a very common form of cancer. However, the chances of survival for a thyroid cancer patient is quite high compared to other forms of cancer. There are four types of thyroid cancer, namely:

  1. Papillary thyroid cancer
  2. Follicular thyroid cancer
  3. Medullary cancer
  4. Anaplastic thyroid cancer

Hyperthyroidism

This condition is caused when thyroid glands excessively produce a hormone called thyroxine. The symptoms include a change in appetite, unexpected weight loss, insomnia, fatigue, irritability, frequent urination, increased sweating and heat intolerance. But this condition usually resolves within a few months of relevant treatments and proper medication.

Hypothyroidism

This condition is caused by the under-secretion of the thyroid hormones. It is a very common problem and often stays undetected for years. One of the main reasons that trigger hypothyroidism  is an autoimmune disorder called Hashimoto’s disease. In this condition, the antibodies produced by the body attack the thyroid gland and this results in the glands producing fewer hormones.

Thyroid Symptoms

Sometimes, symptoms of a thyroid disorder are not very obvious. This is because there are various other factors that can induce similar symptoms and usually, the treatment is given according to the symptoms. For instance, excessive tiredness may be associated with sleep apnea, narcolepsy etc, but the underlying symptoms may actually be thyroid related. Some of the common symptoms of the thyroid are:

  • Nervousness
  • Poor concentration and knowledge retention
  • Change in the menstrual cycle
  • Increased heart rate
  • Muscle aches
  • Weight gain
  • High level of cholesterol

Thyroid Treatment

The most common treatment available for thyroid problems like hyperthyroidism is to replace thyroxine with another synthetic man-made hormone called levothyroxine ( or L-thyroxine). It is an injectable and an oral medication that can return the balance in the thyroid glands. Patients will experience a reduction in the symptoms of hyperthyroidism in a few weeks post medication.

Cancer in the thyroid gland could be treated quite successfully with radiation. Thyroid cancer would be difficult to diagnose sometimes as it shows no signs or symptoms. A periodic checkup is essential for preventing such diseases from taking root.

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