Iodine Quick Reference
• Overall context for this topic
• General information
• Program target
• Supplement considerations
• Supplement suggestions
• Testing considerations
Page edition: 2022-10-29
Although this article is public, not all links within it are.
This is a two-part sticky article. Iodine supplementation
must be considered within the context of what is known about
Part 2: thyroid
status. Testing is strongly recommended.
Iodine (element I) is a core program supplement. Due to several modern issues,
iodine intake is subclinical for many people. Your level, on starting the
program, is almost certainly suboptimal. Challenges include:
- low salt mania resulting in reduced intake of iodized salt;
- inland crops, and industrial-scale crops providing less iodine;
- seafood consumption often reduced vs. historical levels;
- iodine out-competed by non-native halogen compound exposure;
- other endocrine disruptors in diet altering thyroid needs, and
- diets no longer include game thyroid glands.
The need for iodine has been part of the program, going back
at least a decade, and is extensively discussed in all the books and
Blog: The Return of Goiters:
on Inner Circle)
Video: A Brief History of Iodine (members)
Book: Super Gut:
starting page 165 of print edition
Book: Wheat Belly R&E:
starting page 248 of print edition
Oral Temperature on Iodine (members)
and Autoimmune Thyroid Conditions (members)
Forum: Megadose Iodine? (members)
Program Iodine Target
Program target is based on a suggested daily intake, ideally
confirmed by complete testing of thyroid status:
to 350 micrograms
(µg, mcg) per day (for adults)
Return of Goiters, 2022-10-25, linked above)
The daily dose is micrograms (µg, mcg) of elemental iodine,
and not the total weight of the iodine compounds
consumed, nor that of the total dosing unit.
For comparison, the U.S. RDA for adult males is presently 150µg, which
is enough to prevent goiter, but has nothing necessarily to do with being optimal.
The program target usually requires an iodine supplement, in one or
more forms, from a very small selection of compounds.
Iodine is needed even you have no thyroid. It is not just for supporting
production of thyroid hormones.⇱ Return to ToC
Do not exceed RDA (150 µg) with an active hyperthyroid condition, or with a reactive
autoimmune thyroid condition (such as Hashimoto’s or Graves). If there is a reaction
to increasing dietary iodine, back off on the dose until the issue is corrected.
Micrograms; not milligrams.
Beware of megadose iodine supplements providing daily doses stated in mg,
if not actual full grams.
Never consume tincture of iodine.
It is a topical antiseptic and is frankly toxic if consumed orally.⇱ Return to ToC
Before considering a supplement, have a rough idea of how much iodine you get from
foods. If you eat a lot of wild-caught seafood (i.e. daily), you might not
actually need to supplement. Unfortunately, many otherwise-useful sources of
nutritional breakdowns entirely neglect to report iodine content.
The majority of iodine supplements on the market are megadose, and need to
be avoided (or highly diluted). Iodoral® and Lugol’s are the most common of
these, but even brands you’d expect to be modest dose
(such as Mercola, 1500µg) can exceed suggested optimal.
Radio-protective potassium iodide tablets are likewise too high in iodine
for use as a supplement.
The supplement formulation suggested is:
“i.e., dried seaweed, essentially mimicking the natural means of intake
that also provides iodine in all its varied forms (iodide, sodium iodate,
potassium iodide, potassium iodate, iodinated proteins, etc.)”
Keep the container well sealed to prevent out-gassing of the iodine.
Refrigeration might be helpful. Mind the expiration date at time of purchase.
Capsules, tablets, or drops that are specifically for use as iodine supplements
might be suitable for use until a kelp product can be located, but mind the
total dose of elemental iodine. Most products on the marker are either just
RDA, or are far too high in iodine.
Low dose potassium iodide drops can be very useful in challenging a receding
autoimmune thyroid condition. Look for a product that is 50 µg
elemental iodine per drop (or less).
Supplement forms that are definitely suboptimal include the megadose products
warned about above, plus:
Due to the way this these sheets are formulated, packaged, stored,
displayed, and the ways in which they are consumed at home, and rate at
which they are consumed, the iodine is usually
long gone before you eat it.
- Iodized salt:
In modern life, these salts are used too slowly to provide even
RDA dosing. The iodine evaporates before the container is even partially
used. Further, if you’re using an ancient
mined salt, or even modern
sea salt, these are typically not fortified with iodine.
Eating enough seafood to obtain program target for iodine is
tricky. Even with authentic wild-caught (higher food chain) fish,
that could easily present a toxin exposure risk (mercury being only
one such). Too much market fish today is farmed, if not GMO, and the
iodine content is anyone’s guess. Eating enough wild baitfish has
other issues, particularly when canned.
There is no specific advice on time of day to take iodine.
If taking selenium, the iodine can be taken with it.
Take any iodine supplements at a different time than any probiotics
or live-culture fermented foods, due to the antibiotic effect of iodine.
Where no autoimmune or hyperthyroid conditions are suspected, consuming
the program target amount of iodine can commence with the program.
Where a reactivity is being challenged, adjust no more sharply than
50 µg per every 4 weeks.⇱ Return to ToC
What iodine supplement to use hinges on how much you are already obtaining
from other sources, such as a multivitamin, seafood and coastal crops.
A multivitamin is likely to be providing RDA (150µg).
For that, only another 150 or 200µg needs to be provided.
Unfortunately, the ConsumerLab testing service has not yet tested
iodine supplements (other than as the radioprotective KI compounds,
which are not suited to our purposes), but they have tested some
kelp products and they have rejected several of them for containing
177%-207% of listed iodine, which is a material problem.
In a capsule forum, Solgar brand is worth considering, although the dose
reported by CL (200µg) doesn’t appear to match the product
currently available (225µg). In a full-dose product the
NOW Foods 325µg product looks interesting, but hasn’t been
independently verified.⇱ Return to ToC
Specifically testing for iodine is not presently recommended in the program,
both because the
available tests aren’t terribly useful, and because what
matters is thyroid status, for which various useful tests
are available. They are covered in the Thyroid
Optimization Quick Reference article.
Although an initial thyroid panel is always useful (especially the antibody
tests), wait two months before checking for an initial response to iodine deficiency.
When making later adjustments to iodine intake, wait 4 weeks for re-test
of thyroid status.⇱ Return to ToC