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.
- viji said Very clear explanation. Thank you Dr Kristine!
- Kristine said Thanks, Meghan – I agree! It should be a primary concern, not an afterthought, and we need to...
- Meghan J said Thank you for this post. It’s a topic that is often added as an afterthought to medical schoo...
- Kristine said Thanks, Sumayya!
- sumayya roohi said mantle cell lymphoma is CD 5+.CD 23-, CD 79b+, FMC7 and cyclin D1 +
- Kristine said I would presume so – at least as long as it remained in the blood.
- Kristine said “Open” chromatin means that you can see through the chromatin – it appears fine, l...
- Kristine said Thanks, Julia!! So glad you found it and it was helpful
- mcray aboagye said Thanks
- ikondere julius said thanx so much
- Kristine said No – I’m sorry, we’re all sold out.
- Rachel Nicholson said Are these shirts still available?