Q. I heard that if you ingest too much iodine, you can develop hypothyroidism. Is that true? I’m a little confused about why that would happen .
A. Yes – it is true that too much iodine can lead to hypothyroidism. It seems counterintuitive; you’d think that more iodine would lead to more thyroid hormone production. However, it does seem that there is a link between excessive iodine intake and autoimmune thyroid disease (leading to hypothyroidism).Recently, researchers from China have found that too much iodine leads to an influx of lymphocytes, for some reason, and an increased incidence of self attack on the thyroid:
“…although iodine supplementation should be implemented to prevent and treat iodine-deficiency disorders, supplementation should be maintained at a safe level. Levels that are more than adequate (median urinary iodine excretion, 200 to 299 µg per liter) or excessive (median urinary iodine excretion, >300 µg per liter) do not appear to be safe, especially for susceptible populations with either potential autoimmune thyroid diseases or iodine deficiency. Supplementation programs should be tailored to the particular region. No iodine supplementation should be provided for regions in which iodine intake is sufficient, whereas salt in regions in which iodine intake is deficient should be supplemented with iodine according to the degree of iodine deficiency.”
The underlying mechanism hasn’t been entirely worked out – but there does seem to be a link. So: adequate (but not excessive) iodine supplementation is important in iodine-deficient regions, whereas people in iodine-rich regions should not ingest additional iodine.
- Kristine Krafts, M.D. Assistant Professor, Department of Pathology University of Minnesota School of Medicine May 2013: 81,433 unique visitors.
- Kristine said You’re welcome! Your english is just fine!
- María jose said Thankyou!! That was awsome! Excuse my english!
- Athos A. said sweet!
- Big Al said Amazing website thank you
- thanusha said professor, got a small problem..in the book ESSENTIAL HAEMATOLOGY by A.V Hoffbrand says itz the warm...
- Indra C. Rajaretnam said So glad I found you
- mona talaat said thanks for yours precious knowledges
- zeeshan khan said ‘thank you sO much’ i never realised they had so Close names’ i cud hve confused t...
- 手機外殼 said Hi there! This weblog publish couldn’t be written any better! Searching through this post remi...
- Tana said Thank you^^ This helps me more than you know
- Kristine said Excellent information – thank you! So glad you wrote in.
- Dr. Slope said This is a very nice website. I want to add that DNA damage and DNA mutation are not one in the same....