WEBVTT

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The thyroid gland is a small organ

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surrounding the windpipe below the larynx.

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It produces hormones
that regulate the metabolism

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and are important in helping the body
to grow and mature.

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To produce hormones,
the thyroid gland needs iodine.

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The body cannot produce
this trace element itself

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and needs to absorb it from food.

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If an insufficient amount of iodine
is absorbed,

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the thyroid is unable
to make enough hormones.

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The production of thyroid hormones
is regulated by the pituitary gland,

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a small gland
in the hypothalamus of the brain.

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If the level of thyroid hormones
in the blood drops,

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the pituitary gland produces more

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of the thyroid-stimulating hormone TSH.

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It in turn prompts the thyroid gland

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to increase its production
of thyroid hormones.

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If a persistent iodine deficiency
causes this to fail,

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the thyroid increases
its hormone-producing cells

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and starts to grow.

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Over time, the enlargement
becomes noticeable

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as a swelling on the neck.

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This is known as a goiter or,

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in medical literature, a “struma”.

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As the thyroid gland tissue grows slowly

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and an enlarged thyroid isn’t painful,

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many people remain unaware of it
for a long time.

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Sometimes,
people discover goiters themselves.

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Sometimes, doctors discover them
by accident during an examination.

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An iodine deficiency
is the most common cause of goiter.

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More rarely, it may be caused
by auto-immune disorders

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of the thyroid or thyroid tumors.

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Enlargement of the thyroid
can be prevented

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by eating iodine-rich foods every day.

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Good sources of iodine include milk,
dairy products,

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salt-water fish and iodized salt.

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To sum up:

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The thyroid gland makes
important metabolic hormones.

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The thyroid needs iodine
to produce hormones.

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The body needs
to absorb this trace element from food.

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If the body fails to get enough iodine,

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the thyroid doesn’t make enough hormones.

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To ensure that the body
gets an adequate supply of hormones,

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the pituitary gland
makes hormones that stimulate

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hormone production in the thyroid:

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This causes growth of thyroid tissue

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and the organ increases in size.

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As the most common cause
of goiter is an iodine deficiency,

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eating iodine-rich foods

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is the best method of prevention.