Hypothyroidism Or Under Active Thyroid Gland

Thyroid is a butterfly shaped endocrine gland situated at the base of the neck, below the prominence of the Adam’s apple, resting on the trachea or the windpipe.

It produces three hormones, the two thyroid hormones called triiodothyronine or T3 and thyroxine or the T4 hormones and calcitonin.

The two thyroid hormones control the metabolic rate, synthesis of proteins and the growth and development of children.

Calcitonin is involved in calcium homeostasis that is, it takes up calcium from the blood and deposits it in bones.

The two thyroid hormones are regulated by thyroid stimulating hormone or TSH, which is secreted by the master endocrine gland, the pituitary and the production of TSH in turn is regulated by a hormone called the thyrotropin releasing hormone or the TRH, produced by the hypothalamus, a part of the brain.

It means the final control of the thyroid gland lies with the brain.


Hyperthyroidism and hypothyroidism:

When the thyroid gland produces excess thyroid hormones, it results in hyperthyroidism while when it produces low levels of the thyroid hormones, it results in hypothyroidism.

Hypothyroidism is more common in women and in people over 60.

The commonest cause of hypothyroidism all over the world is deficiency of iodine in food and most countries have tackled the problem by iodising the salt available to its population.

A condition called Hashimoto’s thyroiditis or Hashimoto’s disease, an autoimmune disease of the thyroid gland, is the common cause of hypothyroidism in areas where there is no iodine deficiency in the population. It gradually destroys the gland.



Hypothyroidism can cause a variety of symptoms including fatigue, intolerance of cold, slow pulse rate, anaemia, depression, constipation, dyspepsia, muscle weakness, shortness of breath, hoarseness of voice, hair loss, dry, rough skin, weight gain, heavy menstruation in ladies and weight gain.

Apart from depression, hypothyroidism is also known to accompany severe psychiatric disorders like bipolar disorder, mood disorders and schizophrenia.

It can occur also in pregnancy. Not treating hypothyroidism during pregnancy can lead to delayed growth and low intellectual development of the baby.

Mild or sub clinical hypothyroidism too can cause infertility and miscarriages and can also cause a grave pregnancy condition called pre-eclampsia, a condition in which there is rise in the blood pressure and loss of significant amounts of protein in urine. Gestational diabetes is also seen in hypothyroidism in pregnancy.

In mild or sub clinical hypothyroidism the TSH levels are raised but the thyroid hormone levels are normal.


The diagnosis and the treatment:

Many times, the patient of hypothyroidism is the last to complain about the condition. Often a family doctor may suspect the disease seeing sudden weight gain, deteriorated skin and changes in voice in a regular patient plus probably dulled comprehension reflected in speech and eyes, suspects hypothyroidism.

A doctor will usually suspect hypothyroidism when she or he sees that your skin and hair are dry and rough, there is coldness and swelling of extremities and your heart rate is slow (bradycardia). He may also see delayed relaxation of tendons on testing the tendon reflexes and a kind of non pitting oedema called myxoedema.

Thyroid function lab tests include checking the blood levels of the pituitary hormone TSH and levels of the thyroid hormones T3 and T4.

High blood levels of TSH and / or low levels of T3 and T4 are diagnostic of hypothyroidism.

Hypothyroidism is treated by your doctor with levothyroxine, a synthetic form of the thyroxine hormone or T4.

Levothyroxine is safe in pregnancy.

Your doctor will order regular lab checks of your blood levels of TSH, T3 and T4 (thyroid function test) and adjust the dose of your medication based on the severity of the symptoms and the levels of the hormones, from time to time.

That is the reason why you have to check your thyroid function and see your doctor at regular intervals as advised by your doctor.


The weight gain due to hypothyroidism is of mild to moderate degree. A huge weight gain is unlikely to be caused by hypothyroidism.

Many slimming programs tell people under their treatment that they haven’t lost weight because they have hormonal problems.

The commonest hormonal problems related to obesity are PCOD and hypothyroidism.

It doesn’t matter whether your weight gain is due to PCOD or hypothyroidism.

You still have to eat healthy and at least walk adequately to slim down perfectly and overcome PCOD and most likely help your doctor to reduce your levothyroxine dose considerably.

And people unfailingly do succeed, if they do.

The people on these slimming programs didn’t fail because they had hormonal problems, but because the treatments themselves were unscientific.

Also read the articles, ‘Basics Of Nutrition’, ‘The Science Of Exercise’ and the ‘Simple Steps To Slimming’ and ‘Health Problems Of The Young: PCOD‘ on this website.

Share this post

Leave a Reply

Your email address will not be published. Required fields are marked *