Thyroid Cancer Gland

The thyroid gland sits at the front of the throat. It’s a butterfly-shaped organ perched just below the larynx, or voice box. Usually a bit larger than a quarter and weighing less than an ounce, the thyroid gland consists of two lobes — the “wings” of the butterfly — separated by a thin section called the “isthmus.”

The thyroid’s job is to produce hormones that regulate your body’s metabolism. Your metabolism determines how your body converts food into energy and the rate at which it uses that energy. Because this energy use and activity takes place at a cellular level, every cell in your body depends on thyroid hormones for the information needed to function properly. The thyroid gland’s wide-ranging effect on the body’s metabolism explains why thyroid problems and thyroid disease can affect health in many ways, and why thyroid problems symptoms are so diverse.

Hormones in a Healthy Thyroid

The principal thyroid hormones are thyroxine (T4) and triiodothyronine (T3). T3 is about four times as strong as T4, but a healthy thyroid gland produces about four times as much T4.

The thyroid gland makes these hormones by combining iodine with the amino acid tyrosine. Therefore, in order to prevent thyroid problems, it’s important to get enough iodine in your diet.

In addition to the hormones made by the thyroid’s follicular cells — which regulate heart rate, body temperature and energy level — the thyroid gland also produces calcitonin. Made by the thyroid’s C cells, calcitonin regulates the level of calcium in the blood.

Thyroid Problems: Symptoms and Causes

One way to understand what a healthy thyroid gland does for you is to understand what goes wrong when it starts to malfunction. Since the thyroid regulates metabolism, a change in energy levels is one of the first ways in which thyroid problems or thyroid disease manifests itself.

Hypothyroidism — or an underactive thyroid — is the most common thyroid problem. The symptoms of an underactive thyroid include:

  • Constipation
  • Depression
  • Difficulty concentrating
  • Dry hair and rough skin
  • Fatigue
  • Irregular menstrual cycles
  • Muscle pain
  • Sensitivity to cold
  • Weakness
  • Weight gain.

The symptoms of hyperthyroidism, which occurs when your body produces too many thyroid hormones, include difficulty sleeping, heat intolerance, and appetite changes, along with weight loss in some cases.

Other diseases of the thyroid include goiter and cancerous nodules. Talk to a doctor if you have questions about thyroid symptoms.


Norman, J., MD, FACS, FACE. (2009) Your thyroid gland. Retrieved March 2, 2010, from the Endocrineweb Web site:

Berber, E., MD., et al. (2009). Symptoms of hypothyroidism: Recognizing the most common thyroid disorder. Retrieved March 2, 2010, from the Endocrineweb Web site:

Wrong Diagnosis staff. (2010). Statistics about thyroid disorders. Retrieved March 3, 2010, from the Wrong Diagnosis Web site: