Iodine, Thyroid, and Hormones

A few weeks back I had an appointment with a naturopath and was reminded of the issues that some of us may have with iodine and our thyroids. It was something I started to look into a few years ago, but when my adrenal issues surfaced, I went about healing those first.

But now my adrenals seem fine and yet I’m plagued with issues coming from……somewhere.

After talking with me for an hour, my naturopathic doctor decided to start treating my thryoid glands and one of the treatments is supplemental iodine.

What is Iodine?

I’ve actually talked about iodine here before, it was part of my Superfoods for Fertility post, and yet it seems even I still struggle to get enough iodine in my diet.

Iodine, a non metallic trace element, is required by our bodies for making thyroid hormones. As in, if you do not have enough iodine in your body you can not make enough thyroid hormones. When our bodies are deficient in this element, it affects our thyroid, adrenals, and entire endocrine system. Not only is it important in a fertility diet, it’s essential in the prenatal and nursing period as well. Infant mortality rates start to climb in areas known for iodine deficiency, and it’s also been linked to higher rates of miscarriage and still birth. – Superfoods for Fertility


Iodine is critical to human health. It forms the basis of thyroid hormones and plays many other roles in human biochemistry. While the thyroid gland contains the body’s highest concentration of iodine, the salivary glands, brain, cerebrospinal fluid, gastric mucosea, breasts, ovaries and a part of the eye also concentrate iodine. In the brain, iodine is found in the choroid plexus, the area on the ventricles of the brain where cerebrospinal fluid (CSF) is produced, and in the substantia nigra, an area associated with Parkinson’s disease. – WAPF, Sally Fallon, The Great Iodine Debate

Depending on where you live in the country, it can actually put you at greater risk for an iodine deficiency. As for me – I live in what’s known as the “goiter belt”, an area of the country that struggles with getting enough iodine, due to the lack of fresh seafoods in our diet. (The ocean and the animals that live in it are magnificent sources of iodine)

Before the 1920s, iodine deficiency was common in the Great Lakes, Appalachian, and Northwestern U.S. regions and in most of Canada. Treatment of iodine deficiency by the introduction of iodized salt has virtually eliminated the “goiter belt” in these areas. However, many other parts of the world do not have enough iodine available through their diet and iodine deficiency continues to be an important public health problem globally. (source)

Iodine was added to the salt we routinely eat, which has taken care of much of the goiter issue, but are we still deficient enough to cause other health issues? And what about those of us who choose to no longer consume iodized salt?

Food Sources of Iodine

  • Fruits and Vegetables grown by the sea, including coconut products
  • Blackstrap molasses (158 mcg per 100 grams/3.75 oz)
  • Saltwater fish; haddock, whiting, herring  (330 mcg per 100 grams)
  • Butter from cows fed on iodine rich soil
  • Dried Kelp (62,400 mcgs per 100 grams)
  • Spinach (56 mcg per 100 grams)
  • Milk and dairy products (14 mcg per 100 grams) (at least 20% of iodine is lost during pasteurization so raw is best)
  • Eggs (13 mcg per 100 grams)

Symptoms of Iodine Deficiency

  • Goiter – Without enough iodine in the body, the thyroid enlarges (develops a goiter) as it tries to keep up with demand for thyroid hormone production.
  • Cretinism – a condition commonly characterised by mental retardation, deaf-mutism, squint, disorders of stance and gait, and stunted growth in children of mothers who were iodine deficient.
  • Hypothyroidism
  • Depression
  • Dry skin
  • Fatigue
  • Increased sensitivity to cold
  • Menstrual cycle abnormalities
  • Thinning and brittleness of the hair and nails
  • Unintended weight gain
  • Weakness

Iodine deficiency has also been tied to fibrocystic breasts and breast cancer.

Iodine Patch Skin Test, or Iodine “Painting”

One of the treatments that my naturopath wants me doing right now, is iodine painting, a transdermal supplementation of iodine. Though the use of Lugol’s Iodine Solution I can gage the iodine status within my body and also supplement with iodine at the same time.

Since there is no test that measures the level of iodine in the body, you can actually use this iodine solution to see where your own iodine levels are because your body will only absorb what it needs. And the solution is yellow so you’ll be able to see how long it takes.

Skin Patch Test:

  • Use a yellow iodine, like Lugol’s solution
  • Place a drop of the iodine on a thin area of skin, like the inside of your arm.
  • Note the length in hours it takes to disappear.

If your body has an adequate amount of iodine, the stain should last about 24 hours. Some of it will evaporate and so it’s difficult to know exactly how much you’re absorbing, but it’s a tried and true method used my many holistic practitioners.

The inefficient uptake of iodine from the skin and slow release can be seen as an advantage for those wishing to safely improve their iodine status without medical supervision. This treatment does not seem to provoke a detoxification reaction that often occurs with oral ingestion of Lugol’s. (source)

My patch test lasted for three hours. *ahem*

Over the last 3 weeks I’ve dutifully reapplied the iodine solution (about 3 drops spread over a thin area of skin – about the size of my palm) each time I’ve noticed it has disappeared. It’s slowly been taking longer to disappear, being visible about 8 hours later. I’m hopeful that in a few more weeks I’ll be closer to 24 hours.

There are of course cautions when using iodine, especially when someone has a thyroid disorder.

Taking too much iodine can also cause problems. This is especially true in individuals that already have thyroid problems, such as nodules, hyperthyroidism and autoimmune thyroid disease. Administration of large amounts of iodine through medications (ie Amiodarone), radiology procedures (iodinated intravenous dye) and dietary excess (Dulce, kelp) can cause or worsen hyperthyroidism and hypothyroidism. (source)

There are also cautions against using it internally due to some detoxifying effects from the iodine, so I suggest you work with a holistic health practitioner if you plan on taking it internally.


Have you ever done the iodine patch test? Or worked on supporting your thyroid through supplemental iodine?

More reading:

Thyroid and Homeopathic Iodine

The Great Iodine Debate

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About Donielle

Donielle is an amateur herbalist and natural momma to two littles (with another babe in heaven) after dealing with being less than fertile. She has a passion for nourishing nutrition, natural living, and spreading the word on how food truly affects our health.


  1. Donielle,
    I’ve struggled with thyroid issues for years and in an effort to get off of meds, I sought out ways to help naturally …which was when I turned to Kelp (without any medical/expert supervision). As it turned out for me, that was a very bad decision! It actually caused Basedow’s disease.
    I’m still trying to balance everything, but here is the post I wrote on the effect Kelp can have on an unhealthy thyroid:

    Thanks for sharing your story!

    donielle Reply:

    @Sami Cone, Thanks for sharing your story! It’s another example of how something can help one person and hurt another.

    Sami Cone Reply:

    @donielle, You are so welcome! You are so right – and I am so grateful you’re providing a platform for people to share and learn from.

  2. This is why I caution everyone to go slow and start very small when supplementing iodine.

  3. So, even if we eat unrefined sea salt we may not be getting the iodine that we need? I just assumed that iodine was added to regular table salt because it had been taken out during the refining/bleaching process and because it’s a necessary nutrient, it was added back in, but because sea salt is unrefined, that it would still supply the iodine that we need. Is that a wrong assumption? Thanks for this informative post!

    donielle Reply:

    @Emily @ Live Renewed, People who love sea salt say there is enough in it. People who love refined salt say there isn’t enough. sigh. But I also think that the amount in sea salt is probably not as high as what’s added into refined table salt.

    And yes – even when we eat sea salt, we may not get all teh iodine we need. Because salt isn’t (and shouldn’t be) the only wasy we consume it. It should be in a lot of other foods, but unfortunately with modern agriculture and the way we eat now, we’re not getting enough. Sometimes even with a whole foods diet.

    Elissa Reply:

    From the research I have done there is not enough iodine in salts that don’t have it added, especially since we don’t get much iodine from the other foods we eat. This is sort of a separate issue, but I have also read that Fluoride negates the iodine in our bodies, so if you use fluoridated toothpastes (etc) and drink water that has been fluoridated, you’re potentially destroying any iodine you’ve been taking in to begin with. — as if I needed another reason to dislike fluoride! Thank you so much for your posts on the thyroid Donielle! I’ve recently been doing a lot of research on it trying to get to the root of my infertility issues & have come to realize all the ‘little’ things that I thought were just normal oddities about my body are most likely thyroid related problems! Now, I need to find someone who will actually help me with solving the problem instead of a) telling me I don’t have one or b) trying to stuff me full of synthetic hormones/etc. Thank you for everything you do to inform us!

  4. What kind of iodine are you using on your arm?

    donielle Reply:

    @Honey B., Lugol’s iodine, the 2% version.

  5. will any brand of iodine work?

    donielle Reply:

    @Sarah, I don’t know for sure, my naturopath has me on the Lugol’s iodine (2%). If you’re testing, you need one that’s yellow, which this is.

  6. Interestingly enough, I took an iodine test today at my chiropractor’s office. I didn’t check it throughout the day, but I noticed about 6 hours later that it was completely gone!

  7. When I was dealing with infertility for 2yrs (I’m pregnant now….I charted Crieghton and have a NaPro Doc) I had my thyroid checked to rule that out as a cause and all was fine but when checking into Kelp supliments I read on line that herbs are not regulated by the FDA and most of all the kelp tablets in stores have high mercury levels because of where its havested!
    So anyone concidering kelp just beware!!!!!!


  8. So I was at the food co-op today, and happened to see Iodized Sea Salt. Not sure what to think of that. The brand is Hain Pure Foods, which I’ve never heard of.

  9. I have been relying on iodized salt to get my daily dose in about 1/2 tsp throughout the day. I am skeptical as well since I have read so much about abstaining from iodized salt and using sea or kosher salt. I decided to go with iodized salt to avoid another supplement.
    PS- Thanks Gorgiann for the feedback!

  10. I just had a gastrographin enema, in which they used iodine as the contrast fluid. They tested my thyroid before that, but I haven’t seen the actual results yet. Dr. called it “normal”, but I know that the Dr’s “normal’ can still be sub-par… need to get my hands on the numbers myself…. anyway, I did notice a slight improvement in energy after that. It’s been 3 days. Prior to this I had done a skin test, the dot definitely wasn’t there for 24 hours, but I can’t recall how long it was there. I wish I had checked more carefully. I’d love to know if the gastrographin had a positive effect as a side effect!

    Thanks for this article it’s great.

  11. My mother’s family comes from the goiter belt near Chicago. She went hypothyroid at 13 and I had a goiter as a kid, though my levels always tested ‘normal’. While nursing my second child (and after stress of living in a village in the central African rainforest), I was diagnosed hypothyroid as well. I have now been on synthetic thyroid T4 for 6 years quite happily. Mary Shomon’s book on Fertility helped us manage my thyroid issues through a third pregnancy and I was able to nurse for 9 months. I have switched to sea salt, as the research I’ve seen said it is ‘naturally iodized’. People highly recommend Celtic sea salt, as it is unrefined. It’s been 6 months and I’m feeling great.

    You may want to read up on the issues with autoimmunity and thyroid. This guy says most people, especially those with thyroid issues, should avoid all gluten! Not a popular message, but if it can slow your autoimmune issues, well worth it!

    donielle Reply:

    @Kimberly, Thanks for the extra info and link. My family has actually been gluten free for a couple of years now – and I’ve heard the same thing about thyroid issues, hashimotos especially, that they have to be GF.

    Thanks for sharing!

    Jan Woods Reply:

    @donielle, Gluten free..also could it be the bromide that is now in most breads, pastas and pastry items causing the problems? They used to put iodine in breads, but then substituted bromide in the late 80’s–I think I read this in Dr. Browstein’s book. Bromide leeches iodine from the body!

    donielle Reply:

    @Jan Woods, Interesting! I’m waiting for Dr. Browstein’s book right now so I’ll make a note to look for that info. Thanks!

  12. My DO put me on 25mg of Iodoral when my bloodwork showed a moderately high TSH. At the time I didn’t have any symptoms other than some anxiety. Additional bloodwork later showed that I had high thyroid antibodies. I feel like the Iodine made my situation worse too, as I started developing heart palpitations. I am hoping I didn’t develop Graves (Basedow) disease like a previous poster. My suggestion is to be careful, even IF you are working with a holistic health care practitioner. I have also gone gluten free at the recommendation of my DO, but it hasn’t improved things yet in 2 months.

    Iodine is so confusing, and I am presently looking for a new doctor…

  13. Thought I’d share a couple of links. The first one for additional reading:

    The second one a link to a book by a doctor on Iodine:

    And third a link to where you can get Lugol’s 5% solution which will provide a combination of Iodine and Potassium Iodide in fewer doses: or here:

    Hope this helps everyone! 😀

  14. Oh and according to the reading I’ve done, the patch test is unreliable.

  15. I am not sure the research supports that kelp absorbs mercury, so I am reluctant to believe the warnings. I have been eating raw kelp off the southern California coast for a year now, and when I run out I supplement with iodine/iodide. Both work. Kelp though is really amazing because it concentrates many more important essential minerals than Iodine/Iodide and also binds them so that when you ingest them they are bioavailable. Most mineral supplements are not bioavailable and are merely excreted in the feces. When anyone tells me they took a supplement and BECAME ill generally I am very skeptical. Except for active vitamin A, which is fat soluable and can build a toxicity in your system, most minerals and vitamins are water soluable making it impossible to become ill from them, as no high concentrations of them can ever build up in the body.


  1. […] tree berry to help with my PCOS. To combat thyroid issues I’ve taken kelp but, as of recently, I’ve been actually painting my skin with iodine. I switched to that method because I can tell how deficient I am. Your skin will only absorb as […]