What happens when the thyroid does not work well?


Hypothyroidism is the most common thyroid disease

January is National Thyroid Awareness Month, during which information is disseminated about this small butterfly-shaped gland in our neck. 

underactive thyroid test

The thyroid has many functions in the body. It produces hormones that maintain the proper functioning of the organs. It also regulates the use of energy, for example, how we burn calories and how fast the heartbeats. 

However, sometimes this powerful gland does not work as it should. 

A common problem, hyperthyroidism, causes the thyroid to produce more hormones than the body needs. 

But the most common problem is hypothyroidism, which causes a hormone deficiency that makes the thyroid function more slowly. In the United States, it affects approximately 4.6% of the population. People with hypothyroidism gain weight and feel tired, although some do not have any symptoms. 

Hashimoto's Disease and Hypothyroidism 

The most common cause of hypothyroidism is Hashimoto's disease. It is an autoimmune disorder, that is, the immune system attacks the thyroid and causes inflammation. This prevents the thyroid from producing enough hormones and causes hypothyroidism. 

Hashimoto's disease is usually hereditary and affects women more than men. People with other autoimmune disorders are more likely to have Hashimoto's disease. 

Other causes 

Hypothyroidism can also be caused by thyroid surgery, radiation treatment, some medications, and thyroiditis (inflammation of the thyroid). Some people are born with hypothyroidism. This is known as congenital hypothyroidism. 

Women are more likely to have hypothyroidism, as are people over 60 and those with other thyroid diseases. 


If a person has mild hypothyroidism, he or she may feel fine and have no symptoms. People with symptoms may have a swollen face, lethargy, weight gain, cold, decreased heart rate, constipation, depression, and thinning hair. Symptoms are different for everyone, so if you think you might have hypothyroidism, be sure to talk to your health care professional. 


Your doctor can diagnose hypothyroidism and help you manage it. 

The doctor will ask about your symptoms, perform a physical exam, and order blood tests that measure levels of thyroid stimulating hormone (TSH) and antibodies. In Hashimoto's disease, high levels of antibodies in the blood indicate that the immune system is attacking the thyroid. 

If the thyroid is enlarged and causing hypothyroidism (something known as goiter), the doctor may order an ultrasound to see it better. Rarely, surgery is needed because the enlarged thyroid can make it difficult to swallow. 


Hypothyroidism can usually be treated with an oral medication called levothyroxine, which replaces a hormone normally produced by the thyroid, to regulate the body's energy. 

If your doctor prescribes levothyroxine, take it at the same time each day. 

Your doctor may need to measure your TSH levels several times to make sure the medication is working properly. TSH levels can change during pregnancy, if you have heart disease or if you are on certain hormone treatments.