As an endocrinologist I treat patients with thyroid disorders. The thyroid is a small butterfly-shaped gland just above your collarbone in front of the neck. It makes thyroid hormone, a substance that controls your metabolism.

An enlargement of the entire thyroid or any part of the thyroid such as a fluid-filled cyst or a solid nodule is called a goiter. Thyroid function is frequently normal in patients with goiter, with no other symptoms except a bulge in the neck.

But a goiter may be associated with an increase in thyroid hormone which is called hyperthyroidism, where your metabolism can be very fast and this is associated with weight loss, palpitations, sweats, tremors of the hands, feeling warm and characteristic eye changes (stare).

If the goiter causes hypothyroidism, this is the opposite of the previous condition. Having less thyroid hormone, metabolism is slower, leading to weight gain, slow heart rate, constipation and feeling cold.

There are many misbeliefs about goiter. It is not caused by shouting, singing, drinking cold water, lifting heavy things, straining with activity or childbirth, or from eating certain foods. You can do all these things without causing your thyroid to become enlarged.

The most common cause of goiters worldwide is a lack of iodine in the diet, which is needed to make thyroid hormone. Other causes are autoimmune disorders where antibodies produced by your immune system mistakenly attack your thyroid gland as in Hashimoto’s thyroiditis or when the immune system causes an overproduction of thyroid hormone as in Graves’ disease.

Pregnancy can also cause the thyroid to enlarge slightly, and thyroid problems can occur with the hormonal changes of pregnancy and menopause. Certain medications can also stimulate the thyroid or damage it, such as amiodarone and lithium. Exposure to radiation through radiation treatments to the head and neck also increase the risk of developing a goiter.

When a nodule is found in the thyroid, the concern is always the possibility of cancer, although most thyroid nodules are benign and non-cancerous. A neck ultrasound is the best imaging test to take a closer look, and depending on the appearance and size of the nodule, an ultrasound-guided fine-needle aspiration biopsy (FNAB) can be done. 

Fortunately, most thyroid cancers are slow to grow — and slow to spread or metastasize. Complete removal of the thyroid or a total thyroidectomy is recommended for high-risk patients, and this includes Filipinos. And unlike some cancers that require several courses of chemotherapy, a single dose of radioactive iodine (RAI) in a capsule may be all that is needed in thyroid cancer to destroy any remaining thyroid tissue. 

Sometimes a goiter can become so big that it causes difficulty swallowing and breathing. Even if this is not found to be cancer, surgical removal of part or of the whole thyroid may be needed to provide relief. Other treatments include injection of ethanol into a cyst or nodule, or a procedure called radiofrequency ablation (RFA) which uses radio waves to create heat that can reduce the size of thyroid nodules.

Patients who have their whole thyroid removed are considered hypothyroid and have to take thyroid hormone (levothyroxine) replacement for life. Thyroid hormone should be taken regularly, first thing in the morning on an empty stomach, usually upon waking so you don’t forget. Take it only with water and wait at least 30 minutes before taking any other food or medication. Even if you don’t eat breakfast, the thyroid hormone should be taken every day.

If you think you have a goiter, consult your doctor to get the proper diagnosis and timely treatment. If you are prescribed thyroid hormone or other medications, remember to see your doctor regularly for follow-up tests and dose adjustment. Thyroid cancer patients also need blood tests done every six months to check that the cancer has not recurred.