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Hypothyroidism FAQ

Answers to your most common questions

What is hypothyroidism?
Hypothyroidism is a condition in which the body lacks sufficient thyroid hormone. Since the main purpose of thyroid hormone is to "run the body's metabolism," it is understandable that people with this condition will have symptoms associated with a slow metabolism.

The estimates vary, but approximately 10 million Americans have this common medical condition. In fact, as many as 10% of women may have some degree of thyroid hormone deficiency. Hypothyroidism is more common than you would believe, and millions of people are currently hypothyroid and don't know it.

What are the symptoms of hypothyroidism?
Recognizing the symptoms of hypothyroidism is extremely important. The sooner you detect the symptoms, the sooner you can receive proper treatment to manage the disorder.

Below are major symptoms associated with hypothyroidism.

  • Fatigue
  • Weakness
  • Weight gain or difficulty losing weight
  • Coarse, dry hair and dry skin
  • Hair loss
  • Sensitivity to cold
  • Muscle cramps and aches
  • Constipation
  • Depression
  • Irritability
  • Memory loss
  • Abnormal menstrual cycles
  • Decreased libido

You don't have to encounter every one of these symptoms to be diagnosed with hypothyroidism. Every patient's experience with the disorder is different.

To learn more, please read our article on the symptoms of hypothyroidism.

What causes hypothyroidism?
The most common cause of hypothyroidism is Hashimoto's thyroiditis, a form of thyroid inflammation caused by your own immune system attacking your thyroid gland. But this isn't the sole cause of hypothyroidism—there may be a variety of other reasons why you have developed the disorder.

To get more details on this, please read our article on the causes of hypothyroidism.

What are the risk factors for hypothyroidism?
If you're concerned about your risk of developing hypothyroidism, there are two main factors to consider—age and sex. Your chances of being hypothyroid increase with age, and they are greater if you're a woman. Hypothyroidism occurs primarily in women older than 50.

Besides age and sex, your risk for hypothyroidism is increased if:

  • You have a family history of thyroid disease or any autoimmune disease
  • You have type 1 diabetes or rheumatoid arthritis, or other autoimmune disorders
  • You have taken anti-thyroid medications (a treatment for hyperthyroidism) or have been treated with radioactive iodine (a treatment for thyroid cancer)
  • You have had thyroid surgery (you had your thyroid removed to treat thyroid cancer)
  • You have been exposed to radiation to your neck or upper chest area

How is hypothyroidism treated?
There are various treatments available, but the basic concept is the same—and it's known as thyroid hormone replacement therapy.

If you are prescribed a form of thyroid hormone replacement therapy, the goal is to compensate for the lack of hormone secreted by your thyroid gland. In most cases, you will take a daily dose of T4 in a pill taken orally.

But it's important to understand that every patient's therapy will be different. There's no cookie-cutter dosage or treatment plan when it comes to thyroid hormone replacement therapy. How the body absorbs the hormones, along with the amount of hormones it needs, is so varied. Your treatment plan will be individualistic. As such, you should expect some degree of experimentation when it comes to finding the dosage and form of therapy that works best for you.

Most people take synthetic T4 alone, some people take T4 supplemented with synthetic T3, and a few people take animal thyroid extracts.