T Nation

How Much Iodine is Optimal?


#1

I have a multi that has 150mcg(potassium iodide) and I have kelp pills. I haven't been taking the kelp pills, because I didn't know if that would be too much iodine considering my multi already has iodine. The kelp pills have 350mcg of iodine.


#2

Look up TC's article on that very subject.


#3

Just searched it and the article is no longer there.


#4

Heres one of his articles...
https://www.t-nation.com/training/5-things-youre-deficient-in


#5

I've done a lot of research on this lately. Assuming you don't have any pre-existing thyroid issues, up to 500 mcg would probably be fine. Once you go past that, there seems to be an increase in TSH... an increase in TSH is not a huge deal but it is certainly not optimal, and some researchers even consider the increase as 'subclinical hypothyroidism'. Yes you read that right, there seems to be a fine line between iodine intake, and TOO much can actually be a negative.

A smaller thyroid volume is better than a larger thyroid volume, if I recall correctly. Iodine intake is weird in this regard. More iodine intake in the short-term seems to decrease thyroid volume, while longer-term studies (over months and years) show that those with a lower/more moderate iodine intake actually have smaller thyroid volumes than those with an excessive iodine intake.

Additionally, kelp / bladderwrack is interesting, I recall reading some studies suggesting that it may be good as an anti-estrogenic (reducing 17beta-estradiol levels). I believe this needs more human studies though.


#6

Well for what it's worth when I had a blood test, my TSH was 1.11. That was with taking the multi and some other pills(Zinc, Vit D, Magnesium, Fish Oil) but without the kelp pills. I then had another blood test later on while I was on the kelp pills and my TSH went up to 2.0. They never tested T3, or T4.