Because this treatment causes thyroid activity to decline, you'll likely need treatment later to supply your body with normal amounts of thyroid hormones.

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How likely is it in this current situation that those doses would exceed one rem to the body and five rems to the thyroid?

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Other times, problems such as an electrolyte imbalance (for example, not having enough potassium, magnesium or calcium in your body), flat feet, diabetes, thyroid abnormalities, certain medications, alcohol or Parkinson's disease may be the cause.

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Radioactive iodine treatment may also be used to treat thyroid cancer that recurs after treatment or that spreads to other areas of the body.

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The radioactive iodine is taken up primarily by thyroid cells and thyroid cancer cells, so there's a low risk of harming other cells in your body.

CNN: Thyroid cancer

But the outfit was well-equipped with hand-held radiation detectors, full body suits with breathing hoods and ample supplies of potassium iodide, a preventive against radiation poisoning of the thyroid gland.

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