When you have a gland, it’s wise to be a bit more careful. It’s not so much increase in anti-TPO one needs to worry about, but more anti-TG and TRAb. Especially the first. According to a scientist called Michael Zimmermann, we don’t know if the increase in anti-TG is transitory or more chronic. I recommend him as a serious investigator of iodine. He realizes the importance of iodine.
What Zimmermann also writes, and which is important, is that one sees a sharp increase in anti-TG especially when someone has been iodine deficient for a long time, and then suddenly gets a lot of iodine. One sees this when a country starts iodizing the salt. In the countries where they have started on a high addition from the get go, one has seen a big increase in anti-TG. Whereas in the countries where one has added iodine a little at the time, there has been less increase in anti-TG.
One used to say, high levels of anti-TG didn’t matter that much. But now there are some studies saying, that anti-TG is more dangerous than one used to believe. It has a greater ability to kill thyrocytes than anti-TPO. I write about this here.
This is why I advice starting low and increasing over time if you have a thyroid. And especially if you have functioning thyroid. If you have had Hashimotos for years, your thyroid does not function anymore. Which is why you need thyroid hormones. The gland will be infiltrated, and it will never be healthy again, I don’t think. In that case, there is no danger of further damage to the gland by ingesting Iodine. The gland is already destroyed, more or less. After many years of thyroid disease, I think everybody deserves an ultra sound of their gland. It’s the only way of truly seeing the state of the gland.
If this is the case with you, you have to decide if an increase in antibodies would worry you or not. High levels of antibodies are connected to symptom load. High dose iodine can clear up thyroid antibodies as well. But you never know which way it will go.
If you are just in the beginning of thyroid disease, you have gotten some anti-TPO or your FT4 is becoming too low, under 40% of range, then I think “low and slow” is the safe way to go.