Iodine: We talk a lot about it, but how much do you need exactly? It’s a good thing, but it’s not a magic tonic. It’s just a mineral with a very exacting requirement, and the amount you want to get is what I want to help you determine in today’s article.
Get to know my new approach to iodine in my book Thyroid Reset Diet.
Product Recommendation: The Thyroid Hormone Regulation Bundle is an assembly of fantastic supplements to help support healthy female hormone levels and aid the body’s natural hormone response. Click Here
Iodine: A Quick Summary
What Is Iodine?
What Do We Know About Iodine?
What Are Some Recommended Targets For Iodine?
How Do We Get Iodine?
Iodine Consumption Versus Iodine Balance
How Do You Determine Your Current Iodine Intake?
Action Steps: Determining Your Iodine Requirements
Get Your Iodine Inventory Today
The ideal amount for adults with normal thyroid function is between about 50 and 200 micrograms per day.
Those who are pregnant and lactating need different amounts, and those who wish to reverse thyroid disease need different amounts (which we’ll get into later on).
And, worth considering is that many people have a broader iodine tolerance. They can do okay with more or less, but they are not the same people who are prone to thyroid disease.
So, let’s get to work. Together, we’ll sort out your best iodine levels…
| WHO Level | Types of Illness | Urinary Iodine (μg/L) | |
| 1 | Severe iodine deficiency |
Endemic goiter Congenital hypothyroidism |
< 20 μg/L |
| 2 | Mild iodine deficiency | Pediatric goiter, low rate of adult disease | 20–49 μg/L |
| 3 | Moderate iodine deficiency |
Low rate of adult thyroid disease rate Reversal of autoimmune thyroid disease and hypothyroidism |
50–99 μg/L |
| 4 | Iodine sufficiency | Lowest thyroid disease rate overall | 100–199 μg/L |
| 5 | Above sufficiency |
Iodine-induced hyperthyroidism, autoimmune thyroid disease, goiter, hypothyroidism |
200–299 μg/L |
| 6 | Iodine excess | Hypothyroidism, goiter, autoimmune thyroid disease | > 300 μg/L |
Iodine is a mineral and it is a necessary part of forming thyroid hormone. So, in its absence there simply isn’t enough of an important building block.
Iodine is a pretty incredible element. Of all the elements we use nutritionally, like zinc, calcium, and iron, iodine is in a place of its own.
That’s because it is, by far, the highest energy element (in terms of the number of electrons and protons), and it is also the most chemically reactive — it is powerful stuff we’re dealing with here.
This is all to say that your body takes iodine super seriously, too.
We have known for quite some time that, nutritionally, iodine is required, and that too little is bad. But, we have also known that too much can be toxic.
In fact, in the past, many people died from iodine overdose. It’s why you can likely imagine a medicinal bottle with iodine having a skull and crossbones on it.
What we have is this: A range where there is too little, a range where it is about right, and then we have excessive. At the excessive range, we have enough to where inside the compartments the body wants iodine, it can build up to too much.
Then, we have a toxic state. Toxic is where we have so much, that it becomes harmful to areas outside where we would normally see iodine in the body. This is where it would come to hurt the kidneys, the liver, and the other organs.
Key Insight: While toxic levels of iodine occur much less frequently, what we know now is that there is a very narrow ‘sweet spot’ for iodine in the body. And, and this is where things get tricky, we can easily find ourselves outside of that sweet spot if we’re not careful.
The chart below that I’m sharing with you has a brief rundown of the recommended daily targets for iodine…
| Daily Total Intake Food Servings | Food Servings | ||||
| Approximate goal | Low iodine | Moderate iodine | High iodine | ||
| Birth – 6 months | 110 mcg | Breast milk or formula | |||
| 7-12 months | 130 mcg | Unlimited | 1-2 | Avoid | |
| 1-8 years | 90 mcg | Unlimited | 1 | Avoid | |
| 9-13 years | 120 mcg | Unlimited | 1-2 | Avoid | |
| 14-18 years | 150 mcg | Unlimited | 0-2 | Avoid | |
| Low Range | Upper Limit | Low iodine | Moderate iodine | High iodine | |
| Adults | 100 mcg | 199 mcg | Unlimited | 0 – 2 | Avoid |
| Adults trying to reverse thyroid disease | n/a | < 50 mcg | Unlimited | Avoid | Avoid |
| Adults with thyroid disease – maintenance | 50 mcg | 199 mcg | Unlimited | 0 – 2 | Avoid |
| Pregnant/lactating women | 225 mcg | 374 mcg | Unlimited | 2 – 3 | Avoid |
These are really good targets. We have a lot of evidence to suggest how much iodine is good, and when you have too much or too little.
In short, we get iodine as part of this larger ‘iodine cycle,’ which is a lot like the water cycle. There is about 50-60 mcg of iodine per liter of seawater.
From there, it is taken in by living things, is concentrated, and makes it way higher up the food chain. Higher amounts of it can also often be found in sea vegetables, too.
It also seeps into soils in areas that are close to the ocean. But, most of it makes its way on land through rain water. This is where water from the ocean evaporates, goes into the sky, and drops back down on us. That brings iodine into our soil.
In general, areas closer to the ocean have more iodine, but there are some exceptions.
But, from the iodine in the soil, we then find iodine through plants, animals, and we access it through our diets in that way.
There are differences in the above, because some soils are quite low in iodine. By and large, most human societies adapted to what was present.
Some societies had so little that they would see diseases of deficiency in large amounts of children. They may have an enlarged thyroid, could be born without good thyroid function, or with cretinism (a severe form of deficiency).
In areas like these, we would see higher rates of disease (especially amongst children).
So, what happened in areas that were coastal or where a large portion of local diets were made up of sea vegetables? In most cases, people were able to adapt.
Given a large swath of time, most people can adapt to a broad range of iodine. Not so much individual people, but populations — their group can adapt, survive, and reproduce.
But, if our intake changes within someone’s lifespan, there are noticeable differences in terms of how well we can tolerate iodine.
By and large, those that don’t tolerate iodine that well are those who are prone to go on and develop thyroid disease. There is a really strong connection here.
So what is the difference between the amounts you are consuming vs. the amount that is ideal for you and your needs? What is the right balance? This is a really important concept that I want to walk you through.
Iodine balance is a big-picture concept concerning whether your levels, that are stored inside your thyroid, are:
Even though it is difficult to measure iodine exactly, what we can do is get a good sense of that balance. Here is how:
| Iodine Balance | Low Level | High Level |
| Negative | n/a | < 49 mcg/L |
| Neutral | 50 mcg/L | 199 mcg/L |
| Positive | n/a | > 200 mcg/L |
We have learned about that by observing people that do iodine uptake scans.
There are medical tests where people absorb iodine, and then we use radioactive versions of that to see where it went. Someone has to be ‘iodine hungry’ to work well, but the insights here can be pretty valuable.
We know that there are certain ranges where they take it up well, and certain ones where they do not. We also know that those ranges of good iodine uptake are the same ranges where the iodine can fix itself.
Key Insight: As a generalization, someone is in that sweet spot where they can reverse thyroid disease, when they are somewhere under 49 mcg of iodine per gram of creatinine of urine.
There is a helpful tool called ‘iodine inventory,’ where you can gauge what your intake is by putting in your foods, supplements, amounts and all, and that is the most accurate way to see how much is there in your body.
The commonly available iodine tests are really good for populations, but not necessarily for individuals. That’s because they fluctuate so much, it’s hard to discern any meaningful person-to-person insight that you could take from it.
Let’s take a look at the chart below provided by the World Health Organization (WHO)…
This chart identifies six different iodine levels.
The first level has been called ‘severe iodine deficiency,’ and this is such a tragic state. In this state, we might see some of the conditions I mentioned earlier: goiter, congenital hypothyroidism, and cretinism (in the past). This is at the lowest level of iodine intake, and occurs in diets that are generally devoid of any food variety at all.
At this point, the WHO is happy to report that there are no nations on Earth currently suffering from this stage of iodine. It has been all but eradicated as of 2014.
Next up we have level two, otherwise known as ‘mild iodine deficiency.’ Here, we do still see some higher rate of goiter amongst children, but we see less rates of thyroid disease amongst adults. This is between 20-49 mcg of iodine per liter of urine.
This is a level that is also quite uncommon across the globe. Only a handful of nations are presently dealing with it.
The third level is referred to as ‘moderate iodine deficiency.’ Data has shown that we do see slight elevations of goiter, sometimes in children but not always, but this is where adult thyroid disease can often reverse.
On a long-term basis, this is not where you would want to see yourself. But, it can be a great starting point when it comes to resetting thyroid function and putting yourself on a path to better thyroid health.
Essentially, this is where you are in a negative state of iodine balance. Basically the amount of iodine coming in, is less than the amount trapped inside your thyroid.
This allows your thyroid the opportunity to get rid of any iodine that is constantly being held there and causing issues. It’s a moment in time that effectively allows your thyroid to regroup, and your health is better for it.
This is called ‘iodine sufficiency.’ By and large, this is the target for non-pregnant and non-lactating adults. We see lower rates of thyroid disease here.
Keep in mind, not so much reversal of thyroid disease, but low rates of it, overall. This is square within the recommended daily intakes for non-pregnant adults.
Above level four, we have ‘above sufficiency.’ At this stage, we begin to see thyroid disease go back up. We will see iodine-induced hyperthyroidism, autoimmune thyroid disease, and even goiter (which we end up seeing on both sides of the spectrum).
As I mentioned before, this is not for everyone. There are many people at this level, and because they are not prone to thyroid disease for whatever reason, they can be perfectly healthy at this stage.
Those prone to thyroid disease, though, this window is a big deal. And, ultimately, that’s the iodine paradox. It is not a massive amount of iodine, but it is an excess amount that can have a big impact on your overall health.
Finally, we have ‘iodine excess.’ This is where diseases pick up, quite consistently, in populations. This is generally above 300 mcg of liter in the urine.
In most cases, that equates to 300 mcg per day of daily intake. And, to be quite honest, that’s not all that much!
It is easy to get to that point. It’s even easier when we think about how much iodine we can find in processed foods and many multivitamins. That is why it’s imperative to take a multivitamin pack (like the Daily Reset Packs) that are iodine-free!
The best place to start is with the Iodine Inventory. This is your opportunity to really dive deep into how much you’re getting, based on your daily habits and exactly what you’re consuming. Ultimately, this can give you a pretty clear picture of where you stand.
But, what is important to keep in mind is that your current levels don’t predict whether or not you could benefit from a thyroid reset.
If you have thyroid disease, even if it doesn’t seem like you’re getting too much iodine right now, you still may be in a position where your thyroid function can stand to improve.
We have seen this from the studies of thyroid disease reversal. They have shown that pre-diet iodine levels didn’t predict who would be successful.
But, of those who would not respond to the diet, by and large you can see that post-diet iodine levels could explain that.
Key Insight: Nearly all people that didn’t respond to modulating their iodine were found to still be at a very high iodine level.
That means that, it doesn’t hurt to both check your iodine levels before and after doing a reset. It can help you get a much larger picture of where you are and where you may still need to go.
The easiest action step is getting an Iodine Inventory and seeing what your iodine levels are, and seeing if this could be a way to help reverse existing thyroid disease.
If you are free from thyroid disease, you would be well served to stay at that level for a portion. Stay at iodine sufficiency.
After all, we want some iodine, because it is important it can keep us healthy. So, if you remain stable at that level, you should try and keep it that way.
But, if you have existing thyroid disease, getting to that reversal window can make a world of difference. It has a great chance of helping.
By helping, I mean two critical things. Your thyroid can:
If your thyroid is gone from surgery, or highly shrunk, it may not regrow. But, there is still a benefit, because that excess iodine state can prevent your thyroid from even trying to work.
And, it also makes your cells block thyroid hormone. So, even when you’re on thyroid medication on a long-term basis, you can still benefit here! That’s great news.
As I mentioned, getting a reading on where your iodine levels currently stand is so important. That’s why I am so excited to share this with you — please consider getting a thorough understanding of your Iodine Inventory today by clicking here (Click Here: Start your iodine inventory right now).
P.S. Whenever you are ready, here is how I can help you now:
1. Schedule a Thyroid Second Opinion with me, Dr. C, Click Here for Details
2. Need A Thyroid Supplement Recommendation? Take My Thyroid Specific Formulations Quiz Now
3. Need a Personalized Supplement? Check out My Thyroid Specific Formulations
4. Download and use my Favorite Recipes Cookbook Here
5. Check out my podcast Medical Myths, Legends, and Fairytales Here
Dr. Alan Glen Christianson (Dr. C) is a Naturopathic Endocrinologist and the author of The NY Times bestselling Adrenal Reset Diet, The Metabolism Reset Diet and The Thyroid Reset Diet.
Dr. C’s gift for figuring out what really works has helped hundreds of thousands of people reverse thyroid disease, lose weight, diabetes, and regain energy. Learn more about the surprising story that started his quest.
