The thyroid is a misunderstood gland, often blamed for fatigue and obesity.

       The thyroid gland is our battery; it powers our metabolism and activities.  Like all organs, it can malfunction and, when it does, the effects on the body range from subtle to severe.  Diseases of the thyroid are more common in women than in men and are easy to discover with a simple examination and a few blood tests.
A. Physiology:
      The physiology of the thyroid is simple.  The Pituitary Gland, which is the master gland in the brain, produces TSH (Thyroid Stimulating Hormone), a brain hormone that regulates thyroid production.  If thyroid production is low, the TSH will be high and if thyroid production is high, the TSH will be low.  Measuring the TSH is a useful screening test but, by itself, may not be enough.
      Measuring the individual thyroid hormones (T3) and (T4) is more specific.  (T4) is our reserve hormone and (T3) is our active hormone and our bodies convert (T4) to (T3) to meet metabolic needs.
B. Hypothyroidism:
      When the thyroid fails, it starts to make less hormones than the body needs and that, in turn, causes the body’s metabolism to slow down and our physical energies to diminish.  In mild disease, which is the commonest presentation, the clinical signs may be absent and the patient may feel well.  When this common malfunction occurs, the tests show high TSH + normal T3 & T4 and the condition is known as Sub-Clinical Hypothyroidism.  In severe cases, everything slows down and patients experience fatigue, become constipated, feel cold, lose hair, swell up, look waxy-pale, feel depressed, and become mentally dulled.  In such severe cases the tests show high TSH + low T3 & T4 and if the disease is left untreated, patients become obtunded and go into what is known as Myxedema Coma, which is a life threatening condition.
C. Hyperthyroidism:
      When the thyroid produces excessive amounts of (T3) and (T4) hormones, it speeds up the body’s metabolism, which causes the heart to beat fast, the hands to become shaky, the skin to feel hot and sweaty, the sleep to become disrupted, and the patient to lose weight.  Typically, the tests will show low TSH + high T3 & T4.
D. Goiter:
      When the thyroid begins to fail and produce less hormones than needed, the pituitary (Master Brain Gland) increases the TSH (Thyroid Stimulating Hormone), which causes the thyroid to grow in size in order to meet the higher hormone demands.  When the thyroid becomes large enough to be seen bulging in the neck, it is called a goiter.
E. Thyroid Cancer:
      When the thyroid grows one or more nodules, one should make sure that the nodules are not a form of thyroid cancer.  There are complex tests for such nodules that will usually identify them as benign or malignant.
F. Therapy:
      The treatment for the low thyroid states (Hypothyroidism) is to give thyroid hormones, which are available as tablets.  The hormones are dosed to return the TSH (Thyroid Stimulating Hormone) back to normal and usually the treatment is life long.
      The treatment for the high thyroid states is to slow down the thyroid with anti-thyroid pills, with thyroid radiation, or with thyroid surgery.  These decisions are complex and should be made by doctors who are experts in that field.
      The treatment for goiter is complex.  If it does not respond to oral thyroid hormones, surgery may become necessary and such decisions should be left to the experts.
      The treatment for thyroid cancer is usually curative if the disease is discovered early and may involve both surgery and radiation followed by life-long suppression with oral hormones to prevent relapses.
G. Myths:
      Most weight gain and fatigue are not caused by low thyroid states and treatment with thyroid pills will do no good.
H. Dangers:
      Excessive treatment with thyroid pills to reduce weight and combat fatigue is harmful because it can cause the bones to lose calcium and break (Osteoporosis) and the heart to fibrillate (Atrial Fibrillation), which can cause strokes and death.