This article is from the Big Folks Health FAQ, by firstname.lastname@example.org (Sharon Curtis) with numerous contributions by others.
The thyroid gland is located in the neck, just below the Adam's apple.
This produces thyroid hormone. Too much thyroid being produced
is hyperthyroidism; too little is hypothyroidism.
Symptoms of hyperthyroidism (not all are necessarily experienced)
include weight loss, a fast pounding heartbeat, frequent bowel movements,
inability to sleep, nervousness, muscle weakness and fine tremors
of the fingers and tongue.
Symptoms of hypothyroidism (not all are necessarily experienced)
include weight gain, tiredness, depression, feeling run-down,
skin/hair/nails may grow more slowly and be more brittle, constipation,
anemia, fatigue, loss of appetite, irregular or absent menstrual periods,
swollen ankles, puffiness about the face, elevated cholesterol and, possibly,
hypertension. To put it succinctly, the metabolism is just not working
Thyroid problems are fairly common, but not everyone with them has
been diagnosed. It is estimated that at least 6 or 7 million Americans are
hypothyroid. Hypothyroidism is 4 times more common in women than in men.
Although a small proportion of large people do have thyroid problems,
not every large and/or tired person has a thyroid problem.
Diagnosis of hypothyroidism is by a simple blood test, and treatment
is with tablets of levothyroxine, a synthetic thyroid hormone.
More information can be found on-line, for example at the on-line service
provided by the Santa Monica Thyroid Diagnostic Center
(URL is http://www.thyroid.com/ ).