What is hypothyroidism?

Hypothyroidism is the most common type of thyroid disorder. It means your thyroid gland is not active enough. This tiny gland is found in the front of your neck. Its job is to make thyroid hormone. If the gland is underactive, it may not make enough thyroid hormone.

Thyroid hormones control how your body uses energy. They affect almost every organ in your body. When your thyroid doesn’t make enough of these hormones, parts of your body slow down.  

What causes hypothyroidism?

The most common cause of
hypothyroidism is an autoimmune disorder. This means your immune system starts to attack
itself. It makes antibodies against the thyroid gland. The normal thyroid cells are
overrun by white blood cells and scar tissue. Another cause may be treatment for an
overactive thyroid gland. That may include radioactive iodine therapy or surgery.
Hypothyroidism may also develop shortly after pregnancy.

A condition called secondary hypothyroidism can also sometimes happen. It’s when your pituitary gland stops working. The pituitary gland then no longer tells the thyroid gland to make thyroid hormones.

Newborns are tested at birth for
hypothyroidism. This condition is called congenital hypothyroidism. It must be treated
right away. It can affect a baby’s brain and nervous system.

Who is at risk for hypothyroidism?

You may be more likely to have hypothyroidism if you:

  • Are a woman
  • Are older than age 60
  • Have had thyroid problems or thyroid surgery in the past
  • Have a family history of thyroid problems
  • Have certain conditions, such as type 1 diabetes or rheumatoid arthritis
  • Have Turner syndrome, a genetic condition that affects women
  • Are pregnant or have had a baby within
    the last 6 months
  • Have an iodine deficiency. Your body needs iodine to make thyroid hormone.

What are the symptoms of hypothyroidism?

Symptoms are different for each person. They are usually hard to notice and start slowly. They may be mistaken for symptoms of depression. Here are the most common symptoms and signs:

  • Dull facial expressions
  • Tiredness and lack of energy
  • Not being able to handle cold
  • Hoarse voice
  • Slow speech
  • Droopy eyelids
  • Puffy and swollen face
  • Weight gain
  • Constipation
  • Sparse, coarse, and dry hair
  • Coarse, dry, and thickened skin
  • Hand tingling or pain (carpal tunnel
  • Slow pulse
  • Muscle cramps
  • Joint pain
  • Sides of eyebrows thin or fall
  • Confusion
  • Increased or irregular menstrual flow
    in women

These symptoms may look like other health problems. Always see your healthcare provider for a diagnosis.

How is hypothyroidism diagnosed?

Your healthcare provider will ask about your past health. You will
also need a physical exam. Blood tests can also help diagnose hypothyroidism. They can
measure the amount of thyroid hormone and thyroid-stimulating hormones in your