In terms of animal feed, perhaps it is a North American thing, and supplementation is not used extensively in other areas(Europe, Asia,..)?
How Excess Iodine Is Undermining Thyroid Health and What to Do About It — Interview with Dr. Alan Christianson and Ashley Armstrong
Story at-a-glance
While iodine fortification in salt was introduced in the 1920s to prevent goiters, this intervention led to a dramatic increase in thyroid disease
Modern food production and industry has created widespread iodine overload through multiple sources: iodized animal feed, dairy cleaning practices, processed foods, personal care products and supplements
High iodine intake has been linked to increased breast cancer risk, particularly in populations with overexpressed sodium iodide symporters, contrary to earlier beliefs about iodine's protective effects
Thyroid antibodies are more predictive of thyroid symptoms than T4 or TSH levels alone, and genetic variations significantly influence how individuals metabolize iodine across generations
To reduce iodine exposure, limit processed foods, choose dairy and eggs from non-iodine-supplemented sources, review your personal care products and track your overall iodine intake
Sources of Excess Iodine Beyond Table Salt
The underlying sources of modern iodine overload isn't limited to fortified table salt. Christianson and Armstrong shed light on various sources contributing to excessive iodine intake:
1.Animal feed — Conventionally raised livestock are routinely supplemented with iodine, significantly increasing iodine levels in animal products. Armstrong emphasized that if animals are supplemented with iodine, the iodine levels in products like eggs increase five to 10-fold.
2.Dairy cleaning practices — The dairy industry commonly uses iodine-based disinfectants to clean teats and equipment. Although a hot water rinse helps mitigate iodine residues, the pervasive use of iodine teat dips introduces an additional, often unnoticed source of iodine into dairy products.
3.Processed foods — Iodine additives in processed grains and salt heavily fortify the food supply, making it challenging to control individual iodine intake if you consume processed foods. Christianson noted that many processed grains contain iodized dough conditioners. Even those that don’t explicitly list iodine often have significant levels when tested.
4.Personal care products — Iodine is prevalent in numerous personal care products, including some acne treatments, contributing to daily iodine exposure without consumers' awareness. Armstrong pointed out, "Many common acne treatments contain a lot of iodine because of its antifungal and antimicrobial properties."
5.Seafood and kelp supplements — While ocean-based seafood is a natural iodine source, fishmeal is also a common protein source for cattle feed, which increases iodine levels in eggs and dairy products.
By Dr. Joseph Mercola
Dr. Joseph Mercola:
Welcome everyone. Dr. Mercola, helping you take control of your health, and we've got part two. And this time we invited one of my favorite guests of all times, which is Ashley Armstrong, my partner in crime to... We revamped the entire agricultural system for the benefit of everyone here watching this. But we're here because we're both passionate about thyroid and we just happen to have on Dr. Alan Christianson, who is, in my view, the premier expert in the world on this topic. And he's personally helped me out, and I'm confident, when I shared this with Ashley, she says, "I got to be on the call next time." I says, "Great, this is going to be fun." I've done a podcast with two guests before, but they've been frequent, but this one's going to be great. You're going to love it.
And if you don't know who Ashley is, she, of course is, she has her own podcast, and she is the founder of Angel Acres and pivoted from her engineering degree to be a regenerative farmer and help create a system, a system to produce some of the healthiest food on the planet in the most ideal way. And she works with a lot of the Amish farmers. She's networked all across the country with them, and she's scaling up, and many of you now are getting her products in. We're just so happy that she's committed her work to do this and happy that she's here because she's a big fan of Ray Peat and has a really solid understanding of thyroid, which we've never discussed other than superficially. But now we're going to go deep. So welcome and thank you for joining us, both of you.
Ashley Armstrong:
Thanks for having us on.
Dr. Alan Christianson:
Happy to be here.
Dr. Joseph Mercola:
All right.
Ashley Armstrong:
And I'm excited because the food production really connects here. I've got quite a few questions at the end, but the iodine content, which impacts thyroid health, has significantly increased in our food production system over the last 20 to 30 years.
Dr. Alan Christianson:
Spot on.
Ashley Armstrong:
Excited to dive into that as well.
Dr. Alan Christianson:
That'll be fun.
Dr. Joseph Mercola:
And I think my observation or takeaway from our last interview, Alan, was that this was modern healthcare system, public health attempt to correct nutritional deficiencies. And what they've done, they've ruined this in three metals, fluoride, iron, and iodine. None of those should be in the food supply added as a supplement. We don't need them as fortified foods, and that's caused so many problems. So maybe we can start there, because that seems to... From digesting information and really meditating and implying a person, since our last conversation, it's become obvious to me that the nexus, the origin of this epidemic, massive epidemic is fortification of the food specifically with iodine. So, can you comment on that?
Dr. Alan Christianson:
Sure, sure. So historically, in the recent past, in the '20s, 1910s, they were trying to recruit young men for the Great War World War I. And about a third in areas near Michigan, near the Great Lakes had enlarged thyroids. They weren't eligible. So one of the attempts was to add iodine to foods. 1924, that started. Before then, autoimmune thyroid disease was a rarity in medicine. Most doctors, Joe in med school, there's all these things we re-read about in pathophysiology, and a lot of them we never saw. They were so obscure, and that's what autoimmune thyroid disease was for doctors then. But in the following decade, the rates of it among adult women went up 26 fold, not percent, fold. The rates of it skyrocketed, and there was tons of scathing reports and journal entries written, "Hey, this is a problem. We've just created a big issue here."
Dr. Joseph Mercola:
I'm wondering, what is the normal course of someone who's severely hypothyroid? Hypothyroidism could kill you, a Graves' disease. But hypothyroidism, I think is rare, whatever. I mean, you can get mixed edema, go into coma, but for the most part, you have so many serious symptoms that you're always going to seek medical attention. It's never a medical emergency.
Dr. Alan Christianson:
Well, totally agreed. And for even further along, the autoimmunity is a separate variable from the hypothyroidism. Many people never have frank hypothyroidism, but they're still suffering from the autoimmunity.
Dr. Joseph Mercola:
No, I'm referring to the hypothyroidism they were seeking to treat by the goiters that you referenced
Dr. Alan Christianson:
Oh, they weren't hypothyroidism. They weren't hypothyroidism.
Dr. Joseph Mercola:
They just had goiters? I didn't know that. I assumed they were hypothyroid.
Dr. Alan Christianson:
Nope, just structurally abnormal.
Dr. Joseph Mercola:
Is there any
Dr. Alan Christianson:
They just didn't fit the military criteria was what it was.
Dr. Joseph Mercola:
Oh, that is new. Did you know that, Ashley?
Ashley Armstrong:
No. And it's so interesting because livestock always follow suit. So, they added iodine to the salt then you're saying around the early 1900s?
Dr. Alan Christianson:
1924. There was never a mandatory federal step.
Dr. Joseph Mercola:
100 years.
Dr. Alan Christianson:
But 1924, it started being done on a voluntary basis around the Great Lakes.
Ashley Armstrong:
So, then they did that for human salt, and then they started increasing. They were like, "Oh, well, if humans are deficient in iodine, then animals must be deficient in iodine." And so if you look at any mineral pack, any common conventional mineral packs, they're loaded with iodine.
Dr. Alan Christianson:
Well, so fun thing to add to that point. Totally agree. The UK didn't fortify their salt with iodine in '24, but a decade after us, they started fortifying animal feed with iodine, and they saw the same problem about a decade delayed in humans.
Ashley Armstrong:
Because the same thing. So, Dr. Mercola sent me the link to your guys' last interview, and I think one of the big summary points there was that iodine accumulation is a really big problem that our nation is facing. And like you said, Dr. Mercola, it's one of those government interventions, oops. Like, oops.
Dr. Joseph Mercola:
We're the benefactor of those oops.
Ashley Armstrong:
It's unfortunate because you've got one side of the coin that says, we're still deficient in iodine, and I know of people max supplementing with the iodine that they put on their skin. And then on the other side, we've got
Dr. Christianson who has a ton of experience treating people with thyroid problems and showing, no, it's actually an iodine overdose. All of us are loaded in iodine. So, I can understand people's frustrations. As a social media user, as someone who's just trying to get healthy, they see drastically different views, and I understand how frustrating that is for people. And that's one of the things that I like to try to break down into simplistic terms.
And I hope we can talk about this a little bit more today, because I think epigenetics could also be playing a role too. Because imagine if you're born in a womb that has higher level, you're exposed to higher levels of iodine, and then you supplement with iodine, your food contains iodine. It's like similar thing with PUFA accumulation. We've changed the fatty acid profile inside of us. We're accumulating iodine generation after generation after generation. And so I would love to dive into, at some point in this conversation, practical take-home points of how one can address their own iodine overload problems today.
Dr. Alan Christianson:
You just opened up half a dozen wonderful discussion points.
Ashley Armstrong:
I know. I know.
Dr. Joseph Mercola:
Before we go there, I want to share one thing about acid.
Ashley Armstrong:
Because I think it's helpful... People were very confused. Because there's people all over the internet saying, "You're deficient iodine. Your thyroid problem is due to low iodine intake." And I think it's important for people to understand that that could actually be causing them a lot of harm with their iodine supplementation. And that's one thing I appreciate about you is step one, maybe assess your supplements. What do your supplements contain? What medications are you taking? Because that's an easy thing you can just take away potentially.
Dr. Joseph Mercola:
It's also... I'll let you go on, I'll just comment on this one thing. It's also the food. And I get a big portion of my food from Ashley's farms, and the first thing I did was connect her after our interview and said, "Ashley, what do you clean the breast of your cows with?"
Ashley Armstrong:
Teats.
Dr. Joseph Mercola:
And they were using I iodine or some of them were, weren't they?
Ashley Armstrong:
So, for the audience, you have to clean teats, you have to clean milking equipment. That's just good practice. And so unfortunately, another thing in addition to supplements and food and iodine in our salt is we've also moved into iodine based disinfectants all over the place. And there are alternatives. It's just iodine has been widely accepted in the dairy industry as cleaning off the teats. So, you do iodine teat dip. Well, I would say
about 40% of our dairy producers were using iodine teat dip, but they were following that with the hot water rinse. So, I'm not too concerned about it. However, I told them we're going to switch to just hydrogen peroxide with the warm water rinse or vinegar.
Dr. Joseph Mercola:
Perfect.
Ashley Armstrong:
So, there's so many different options that you can use for perfectly acceptable disinfectants. It's just for some reason, iodine, you walk into an agriculture store and you go to dairy cleaning, and iodine is the most common option there. So, it's just more a little bit education. And most dairy producers are not going to be upset about it. They'll just say, "Hey, can I just use up my current shirt?" Of course, do a hot water rinse after, and then maybe switch to something like hydrogen peroxide.
Dr. Alan Christianson:
So, you bring up a really good point. Before you mention about how, the truth is that yeah, this has been fortified in ways that aren't really needed anymore. But the other side of this is that
iodine, it's a really useful molecule in industrial applications. And because of that, along with fortification, there's a lot of industrial uses or process uses in which it's gotten into the food supply. So those are the main two avenues.
Ashley Armstrong:
It's like estrogen.
Dr. Joseph Mercola:
And in Ashley's case, you're getting food from her and no idea that it's snuck in, the iodine snuck in through this route unless you know the specific details to look for. You've covered almost all of them though in your book and in your work. Go ahead, Ashley, you have to retort to my comment.
Ashley Armstrong:
Chickens and pigs are also heavily supplemented with iodine in their feed. And so, if they're just using a conventional feed, there's quite a bit of iodine added to that, and the amount in an egg can increase five to tenfold based on if iodine is added to the feed. There's no iodine in our feed. I promise. That's a mineral I forgot to look at, which is a good thing when I was formulating the feed. But they're also adding it to beef cattle minerals as well. So just general mineral supplementation, which is a good thing for many livestock. But who is formulating these, who's setting these barriers and requirements for microminerals and iodine levels in these mineral packs? That to me is another concerning thing, because again, we go back to the 1920s, added iodine to the salt. Oops, here we are today overloaded. So at what point are things and mineral packs going to change? I think it just more conversations with Dr. Christianson.
Dr. Alan Christianson:
Well, I'd love to make one real high level comment early on too, is that I don't want iodine to come off as a villain or a bad guy or something that we need to avoid because it's essential to life. We need some. The difficulty is that there are genetic variations. Ashley talked about the epigenetic changes. We know that there's variations in human iodine metabolism. We know humans are adapted to different iodine environments, and those who are adapted to lower iodine environments, they can't tolerate what's even a slight excess and amounts that are harmless for others. So yeah, so many people genetically, and these are all the genes that correlate with those having risks for thyroid disease. So many have a genetic intolerance of slight excesses, and it's easy to get that slight excess. So that's the high-level picture that we're at.
Dr. Joseph Mercola:
I want to pivot back to that goiter because I'm still intrigued with that observation. I did not know that was true, that I thought that someone had this goiter that's enlarged thyroid that almost always correlated with hypothyroidism.
Dr. Alan Christianson:
No.
Dr. Joseph Mercola:
But it's not. And it's downsides
Dr. Alan Christianson:
No. Thyroid goiter's quite common.
Dr. Joseph Mercola:
And that is the thyroid's glands response to lack of iodine is tries to make more, and it's just not working more so it just pumps... It's like exercise.
Dr. Alan Christianson:
Well, that can be a driver of goiter, iodine excess can be a driver of goiter, and in many cases there's no clear trigger.
Dr. Joseph Mercola:
Really?
Dr. Alan Christianson:
Yeah.
Dr. Joseph Mercola:
Wow. So, any ideas what causes it?
Dr. Alan Christianson:
It correlates with exposure to alcohol and tobacco. There's also some gene correlations, but it's about three to 5% of most populations will develop goiters. If there's severe endemic iodine deficiency, the rates are higher. Severe iodine, excess rates are higher. It can overlap with hypothyroidism, but in most cases, there's normal thyroid function.
Dr. Joseph Mercola:
Not related. Yeah, yeah. Not related.
Ashley Armstrong:
Dr. Mercola, I think that Dr. Ray Peat has also mentioned x-rays and radiation.
Dr. Joseph Mercola:
Oh.
Dr. Alan Christianson:
Sure. More of a historical driver, but common thing in the past was that radiation was used for swollen tonsils, and in those cases, just the free radical damage could trigger more damage to thyrocytes and more hypothyroidism and more thyroid enlargement, thyroid cancers.
Ashley Armstrong:
Speaking of Dr. Ray Peat, one thing that I would like to discuss would be, it sounds like on your last interview that you are familiar with the work of Dr. Ray Peat. You're very familiar with the work of Dr. Broda Barnes.
Dr. Alan Christianson:
I wouldn't say very familiar with Ray Peat's work in detail, just the name, the fact that he's around. I'm not in detail, familiar with his work. Very familiar with Broda Barnes's work, but just to put that out there.
Dr. Joseph Mercola:
He's more familiar because he read your Your Guide to Cellular Health.
Ashley Armstrong:
Great. So, I'm heavily influenced by the work of Broda Barnes as well. And granted, it was in a different era. And so, I think that's one of the things I've learned the most from you, Dr. Christianson is, hey, maybe we need to take his work with a grain of salt, not
Dr. Alan Christianson:
Iodine salt.
Ashley Armstrong:
Iodine free salt. Maybe take that with a grain of salt. Because for those unfamiliar with the work of Dr. Broda Barnes, he drastically improved people's health in the early 1900s by supplementing, adding thyroid to their protocols. And he used NDT, so desiccated thyroid, and you can't deny the results that he saw. He saw increasing body temperature measurements. He saw resolution of symptoms. He even saw sometimes structural changes in individual's faces. His work and his book are pretty powerful. But now I start to question it a little bit, learning a little bit more about your work and hey, thyroid supplementation shouldn't be mass passed out. I think it is important that today's thyroid is largely just T4 prescriptions, whereas Broda Barnes was doing a little bit more NDT desiccated thyroid. But I was very curious. I had some notes. What are your thoughts on why he was seeing such improvements in health improvements in symptoms when he was giving his patients desiccated thyroid?
Dr. Alan Christianson:
Sure, sure. Yeah. So many had myxedema, many had overt hypothyroidism and thyroid replacement therapy makes a big difference for those symptoms. Yeah, very straightforward.
Ashley Armstrong:
Okay. Another thought I had was maybe the desiccated
Dr. Joseph Mercola:
Let me just ask one question about that, follow up on that. You had mentioned natural desiccated thyroid, which is what Broda Barnes use, but I don't think that's even available today. Maybe they sell it, but is there a process where they actually take the active T3 out of that and it's just essentially T4?
Dr. Alan Christianson:
No. Part of the United States Pharmacopeia Assays for natural desiccated thyroid requires roughly nine micrograms of T3 per one grain dosage, give or take about 10% in the production process. There's no place in which they can manipulate the hormone content. They assay it, and surprisingly, about half of the raw material cannot end up making it to final manufacture because they assay it and it's just out of stock. They can't really fix it, they just throw it out and use another batch basically.
Dr. Joseph Mercola:
Is that a prescription or can you get that as an overcomer?
Dr. Alan Christianson:
So prescription porcine natural desiccated thyroid. We've got three brands right now in the United States. We've got Armour, Adthyza, and then NP Thyroid, and those are standardized, as I mentioned. There are some over-the-counter versions. Tough thing is just the not standardized.
Dr. Joseph Mercola:
So the prescriptions are standardized. The over-the-counter ones are not.
Dr. Alan Christianson:
Well, the prescription ones, yeah. Again, more than half the batches get rejected when they're assayed. So, we know that they're not effective. And even of those that are accepted, a certain amount do have post-production or recall that occurs. So, when they're watched, they're good. They're not perfect, but it does take a lot of analysis and assay. So, the drawback about nonprescription is just if they're not assayed in some way, we don't know the quality control. There actually have been a few studies done of the over-the-counter versions in which they've been purchased and assayed, and they've had a pretty big, they have active hormone, but it's a pretty wide range.
Ashley Armstrong:
Broda Barnes was... He used Armour. And so, another thought that I had was, Hey, this was early 1900s. The cattle, the pigs, they weren't supplemented with iodine, so therefore their thyroids themselves contained low levels. Now we fast-forward to 2024, soon to be 2025.
All the livestock are supplemented with iodine. Potentially their thyroids are now overloaded with iodine, such as for many individuals. And so maybe the Armour and the NDT, the desiccated thyroids are not comparable from early 1900s to today, and maybe they contain a lot more iodine. Are you aware of any testing of any of that?
Dr. Alan Christianson:
Sure, sure. So actually, the raw material is first assayed based upon iodine content and standardized for 0.2% iodine in the raw material for natural desiccated thyroid. The prescription forms are always porcine. There's really just two manufacturers of the raw material. 1980, the real big shift away from natural thyroid occurred because the standardizing, so there's first assay for the raw material, which still is iodine based, then they're standardizing per hormone content. And that's the second step. The second step didn't occur before about 1985. And in 1980, the problem was that you could standardize natural thyroid per iodine content, but not all the iodine was in the T4 and the T3, four and three or how many iodine atoms are present. There's a lot of iodine separate and in thyroglobulin and in other thyronamines. So, you could standardize iodine and you would get an approximation of active hormone, but far from perfect.
And there was a couple of editorials in JAMA about people who were on treatment for hypothyroidism, which should have been therapeutic, but clearly was not based upon their clinical presentation. They were still symptomatic and their scores were way off. And this was the big push for synthetic T4 only. And the advantage that it had in that era was that all the iodine in synthetic T4 was in the active hormone. So, if you standardized per iodine content, you were standardizing per active hormone. And that was a totally valid argument back in 1980 during the Carter administration. But it's not a valid argument today because the standardizing is based on active hormone, and that's written up in the United States Pharmacopeia.
Ashley Armstrong:
Got it. Well, I think many of the prometabolic, bioenergetic groups these days still do encourage or recommend from time to time the use of thyroid hormone supplementation. I have seen it help a number of individuals, but I do think there seems to be a very fine line. And you brought up a good point, Dr. Broda Barnes in the early 1900s, he saw it helped a lot of people. I would say in the bioenergetics space, there is a gray area of diagnosing hypothyroidism versus subclinical hypothyroidism. And I would say you potentially would say that someone with subclinical hypothyroidism should not be on thyroid supplementation.
Dr. Alan Christianson:
Well, I make a distinction too, between whether something might help someone and whether it may cause long-term harm in ways that might not be apparent. And this would be a difficulty with really everything that has been done until just the very recent past. We're seeing more and more data saying that taking hormones from outside the body, people can feel better, people can benefit in various ways from symptoms, and even with normal levels still may have certain complications. So, if someone feels better, that's always a win. They've always improved their health in some way, but I'd love to have that happen in a way that doesn't take away from their long-term health.
Ashley Armstrong:
Because what Dr. Broda Barnes would talk about would be taking some level of thyroid and monitoring your body temperature, waiting one to two weeks, and then adjusting to try to reach 98.6 degrees Fahrenheit. So that's commonly the discussion of taking exogenous thyroid to boost metabolic rates. And so, I think the biggest takeaway I've learned from you Dr. Christianson, is maybe there are long-term consequences to relying on that. So, I think step one for someone would be, how does one assess that they potentially need thyroid hormone support or they don't need thyroid hormone support? What is an actual reason why they should be on it?
Dr. Alan Christianson:
Well, a distinction I would make is whether it seems to help empirically, it wouldn't be a clear sign that it's safe or beneficial. At some point, the interventions that we can have in natural medicine, like thyroid hormones, they can have a nonspecific stimulant effects. Someone could take cocaine and feel more energized, but not be healthier from that. So yeah, I'd pull apart benefits from that. So, in terms of categories in which the benefit outweighs the risk, that really starts with overt hypothyroidism. So, when we look at the body's chemistry and we see abnormalities, the question to ask is that a compensation or is that a failure? Is that something where the body is doing its best to make due of the current situation or have all the backup mechanisms collapsed? And in the case of overt hypothyroidism, yeah, the brain is begging the thyroid to work.
This is Kirk yelling at Mr. Scott, "Scotty, we got to get to work. Give me more." And Scott's like, "But captain, the engines can't take anymore." So yeah, there's a point at where things decompensate and there the body is no longer in homeostasis. It doesn't have the balance it's trying to achieve. And in that case, external interventions, they're causing more benefit than they are causing harm. And that's where we're at with overt hypothyroidism. That's clearly the case when TSH levels are well over 20 and T4 levels are well below range. There's gray cases that are edging on that, but that's clearly a situation in which there's more benefit than harm.
Ashley Armstrong:
If someone has been on
Dr. Joseph Mercola:
Let me
Ashley Armstrong:
Yeah, go ahead.
Dr. Joseph Mercola:
... put up a question here though, because you brought up a point, Ashley, about the diagnosis and the Broda Barne's focus was on the temperature, and in our last conversation we discussed the, or actually, you discussed, and I learned that unless you have an unusual situation with respect to having your thyroid removed or coming off a thyroid hormone replacement that really don't need to measure the thyroid hormones, there's almost no benefit to it. But what's really crucial is to measure the thyroid antibodies, which is strongly suggestive of the cause of almost all hypothyroidism, which is the autoimmune disease. So how do you pair that against the recommendations by Broda Barnes and many others to measure their temperatures, basal body temperatures? Because I have not had a lot of good success with that, and I was taking thyroid hormone replacement. I'm not now since our last conversation, I'm over it completely. I mean, how do you reconcile that body temperature, especially when you have a low temperature?
Dr. Alan Christianson:
Back in Barnes day. So, 1972, everything changed with thyroid assessment. That's when we learned about how to actually measure
Dr. Joseph Mercola:
Really?
Dr. Alan Christianson:
Yeah. Three pivotal things happened. We were first able to assay high sensitive TSH scores, we were able to assay T3 for the first time, then we're able to learn that T3 was mostly peripherally metabolized. Those all happened within a few months. So, this massive shift occurred in our understanding. During his time, we didn't know any of that. And there weren't. There was quotes from 1918 saying, if someone has these symptoms suggestive of myxedema, why not just give some natural thyroid extract? Funny thing. But in the earliest days, there was natural desiccated thyroid, there was thyroid extract and there was thyroid feeding, and there were thyroglobulin. So, there's like four completely different versions. Thyroid feeding was pretty much just like steak tartare, but thyroid tissue. So it was done in a lot of ways, way back when.
Ashley Armstrong:
Eat a whole fish head.
Dr. Alan Christianson:
Well, yeah, they would take thyroid tissue that was just desiccated and not even processed, just chopped up, just minced basically.
Dr. Joseph Mercola:
Wow.
Dr. Alan Christianson:
But in Barnes day, the difficulty was that, and the quote that I was alluded to from 1918 said, "Hey, if someone has all these symptoms that are looking like myxedema, give them some version of thyroid and see if it helps." And in that era, that was reasonable, given what they knew and given their predictive powers, that was totally reasonable. And there was a lot of nonspecific signs that correlated with hypothyroidism before it was obvious, before it was at the point of myxedema and basal body temperature was affected by that. Since Barnes's time, we've learned that the thyroid basal body temperature connections are very real, but they're not as linear. They're not as tight as one might think. So many who are overtly hypothyroid will have a lower basal body temperature.
And during hyperthyroid storm, people often elicit a febrile response, but there's not a linear increase in basal body temperature as one moves further into hyperthyroidism. That wasn't understood during Barnes's time. He thought that you could use the basal body temperature to titrate the dose of thyroid, and sadly, he died from thyroid overdose. That was probably a big part of it. But we now know that during thyroid storm, there's a fever, but there's not a ratcheting up of temperature as you're getting closer and closer to that.
Ashley Armstrong:
So maybe that's why he had to wait two weeks after the thyroid supplementation to wait for that to come.
Dr. Joseph Mercola:
So, your clinical experience, have you found, ever found benefit to measuring basal body temperature?
Dr. Alan Christianson:
If we were back in the olden days, and it was one more sign along with things, but currently I don't use it. For assay
Dr. Joseph Mercola:
Okay. It makes life easier for all of us.
Dr. Alan Christianson:
... there's some thyroid hormone, whether they're on a good dose of thyroid hormone.
Ashley Armstrong:
So, I've worked with a number of individuals that come from a very restrictive background. So of course, in the modern-day diet culture, wanting to be extra model thin, skinny, lean, there are many women who have been on periods of very restrictive diets, and I'm talking prolonged eating 1,200 calories. And from improving their metabolic rate, we do see a rise in their body temperature as their energy production starts to increase because heat is a byproduct there. And so I've seen it correlate with improved health and just energy production. But I think what you're saying is potentially with thyroid supplementation, there isn't a direct line. It kind of
Dr. Alan Christianson:
What you're saying is spot on. So when someone's in a starvation response, their metabolism is impaired in a lot of ways. They can have a lower temperature, they can be centrally hypothyroid, meaning their brain is putting less of a signal on their thyroid than expected, and they can be peripherally, hypothyroid. These are all compensations. They're not failures, they're compensations. They're always, the body is compensating for having just too little fuel available.
Ashley Armstrong:
Because when I was carnivore low-carb, my body temperature was 96.5 degrees Fahrenheit, and now I'm in the 98s, adding a lot of carbohydrates with an improved metabolism. And so maybe it can just be a sign of general energy metabolism, but maybe isn't the best metric and tool right now for assessing thyroid health.
Dr. Alan Christianson:
Well, another tough thing just to throw in with body temperature is where should someone's temperature be? And what is a normal healthy body temperature?
Our reflex is always 98.6. That's from about a century old German paper. That's not considered a normal, healthy ideal, not that it's bad, but there's just such a larger range of normal than we thought a hundred years ago.
Dr. Joseph Mercola:
What do you think that range is?
Dr. Alan Christianson:
It's probably a solid four or five degrees, and it encompasses
Dr. Joseph Mercola:
Really?
Dr. Alan Christianson:
It goes a little above 98.6, but quite a ways below it for normal healthy adults, of course, menstruation affects that greatly. Many of things can as well. But if you're 98.6, it's not the law anymore.
Ashley Armstrong:
Okay. So curious on the best metrics to assess your thyroid and iodine status. And so, what I've gauged from you would be getting those antibody tests done on thyroid, not necessarily T4, T3, TSH to get the antibody test. But then also I'm very curious to learn more about this urinary iodine to creatinine ratio test. From listening to your work, it seems like those two are really good things to monitor as you're making changes to your diet lifestyle supplement. Can you talk a little bit about how those can be used as metrics?
Dr. Alan Christianson:
For sure, for sure. S
o, nothing bad about the thyroid functional test, TSH, T4, T3, but yeah, they're not predictive for most people of symptoms. There's such a loose correlation between them and thyroid symptoms. The antibodies are more predictive, they're more commonly correlating with symptoms and risks. And simple thing, Joe mentioned about antithyroid peroxidase, antithyroglobulin, there's a couple of others that are available, but those are two by far the most common and most typical that are evaluated. Iodine assessment, this is a tricky thing, and for the last century, there have been tons of researchers just pulling their hair out to what are the best ways to gauge nutritional status of iodine?
And there's a lot of good tools for populations, but because there's so much intra and inter individual variability, there's really no great tools for individuals. Once you're measuring 500 people, it doesn't matter how bad that individual test is, you can gauge that group and make sense out of the group. But applied to individuals, there really aren't metrics and there aren't tests that say, are you getting too much or too little?
But there are good tests to see if you're at a therapeutic range, if you're trying to help your thyroid, if you're trying to reverse a thyroid problem, you can then see if you're at a range in which that's likely to help. And that's the urinary iodine to creatinine ratio.
Ashley Armstrong:
Dr. Mercola, have you ran that test yet?
Dr. Joseph Mercola:
No, I haven't. Yeah. Actually, in our new health coach system, I wasn't really going to focus on that too much because technically it's not that difficult. Compliance to it is somewhat of a challenge because you have to typically make sure you're married to a gallon jug for 24 hours.
Dr. Alan Christianson:
To be precise, it require 24 hour test. But further to your point, the test is not a mandatory thing. Probably the most useful way to gauge one's status is just by being aware of one's intake. If you do a good inventory of your intake from salt, food, supplements, personal care products, you can pretty well know what you're ingesting.
Dr. Joseph Mercola:
And that's free and curative too. You kill two birds with one stone.
Ashley Armstrong:
So, I think that's another thing I appreciate about your work, Dr. Christianson is they're practical take home steps. You outline them and how crucial diet is. Can you talk a little bit about, because we were mentioning earlier, body temperature when you're on a low carb... When you're in a starvation state, your body temperature down regulates as a protective mechanism to down regulate energy production. When it comes to low carbohydrates, how have you seen that impact iodine status, thyroid health, because there's this message in the low carb space that it's well documented that your T3 is lowered when you're on a low carb diet. But many advocates say that that's just the body becoming more sensitive to it. And your reliance on ketones and a change in your body's energy utilization, glucose versus ketones and fatty acids, that diminishes the need for higher T3. What has been your experience with someone going low iodine but also low carbohydrates in improving their thyroid status?
Dr. Alan Christianson:
Well, so as a separate variable, everything you mentioned is spot on. Carbohydrate intake itself can correlate with the body's metabolic rate, and this correlates with insulin production. There's so many times in which insulin is at an excess, but if it's far too low, that can impair the peripheral activation of thyroid hormones. And the body can sometimes see extremely low insulin as a proxy for starvation, even if there's not a deficit of caloric intake, even if someone's eating enough food, but insulin is far too low, their body can start eliciting a starvation response. One of the more dramatic studies was on children put on a ketogenic diet for seizures. And in the study it was adolescent kids.
In the population, the normal baseline rate of hypothyroidism, overt hypothyroidism is about one in 1,250. So pretty rare, less than one in a thousand. But during the course of a two-month ketogenic diet for seizures, the rate of overt hypothyroidism warranting thyroid medication was 27%. So yeah, the one variable was that control groups that were medicated, that still had seizures but were not in the ketogenic diet, didn't have a higher rate of hypothyroidism. So that was one of the more dramatic studies. And we've seen other ones in pediatric populations and others in adult populations that are showing similar results. If one's intake of carbohydrate is radically low even on a eucaloric intake, then yeah, there are central ways and peripheral ways in which thyroid hormones are downregulated.
Ashley Armstrong:
Dr. Mercola, do you have any follow up questions there about
Dr. Joseph Mercola:
No. You can go ahead. Go ahead.
Ashley Armstrong:
Okay. Well, then I'm curious. So, let's say someone believes that they're in a hypothyroid state, their thyroid antibody tests are elevated and they want to make actionable steps forward. I think hopefully that data you shared encouraged people to include carbohydrates that work well for you, support your body's energy metabolism. Insulin is not the bad man that people lend it to be. Of course, we don't want it to be elevated all day long, but spikes in insulin are important for normal functioning, including converting T4 into active thyroid hormone T3 throughout the body. And so, it's not something we need to be afraid of. So, can you talk a little bit more about the low iodine diet that you recommend for people to follow for one to three months? Because I did some playing around on chronometer and I have concerns about choline, biotin, calcium, C15 and a few other nutrients on a low iodine diet. So, I was going to pick your brain on your thoughts on how to mitigate those deficiencies in this phase.
Dr. Alan Christianson:
Those are all excellent points. And to draw upon that, the studies that I've cited were studies that were not meant to put people on a diet that was ideal for their long-term health. It was something that was done short-term for one specific reason. And when I wrote
The Thyroid Reset Diet, I did my best to think about it in ways to where if someone were on a diet like this for three, six or nine months, how can it be more nutritionally sound? How can they cover the bases more thoroughly? You brought up several excellent points. And the drawback is that most people, their sources of choline, C15, calcium are correlated with sources that are quite high in iodine from commercial sources. So, if people have more sources of eggs and dairy that don't have unusual amounts of iodine, that can make it even easier for them to maintain nutritional validity. And if your work is providing that, that'd be a wonderful benefit for us all.
Ashley Armstrong:
I was honestly, before your work, I didn't even know that eggs and dairy could be high in iodine. It's just not talked about. And
I pulled up quite a few studies. It is alarming the difference in iodine levels between what the animals are fed, what they're supplemented with and disinfectants and what they're cleaned with. And for example, potassium iodide and calcium iodate, those are two very common things that dairy cows are supplemented with in their feed rations. In a confinement dairy, the cows are in more barn stalls and they're fed a daily ration. So, it's to the science. These confinement barns operate very efficiently. They know exactly how much all cows eat, what they need to get each day, so they're formulated in their buckets that they eat out of. And I had no idea the amount of iodine that these dairy cows are intaking through their daily rations.
And again, is this an oops thing, just like how the government added salt to our iodine, we're now loading animals with iodine? And I had no idea that this had the results that it does. Like I said earlier, you can increase the amount in eggs by five to tenfold just by having iodine in the feed. And with dairy, there were some that were 10 to 15 fold depending on the combination of what they ate, what the disinfectant was used to clean off the milk equipment or care. So I guess just yet another reason to know where your food comes from, to know your farmer, to ask these questions. But can you touch briefly on other... So be mindful of your dairy, where your dairy is coming from, your egg intake. What are other high iodine sources? Oh, seafood.
Dr. Alan Christianson:
Yeah, ocean-based seafood.
Ashley Armstrong:
Okay.
Dr. Alan Christianson:
Back to your last point, just two more things to highlight upon. One of which is that the amount in those foods is incredibly variable. There's some samples that don't really have inappropriate amounts, but many do. So, when I put foods in those green, yellow, and red light categories, the thought wasn't what is the average intake or what is the listed intake from one source, but really from many, many sources, what's the reasonable possible amount that could be and exposed to? And if someone could get too much, I would call those red light foods. One more thing I'd love your feedback on, many of the sources I read also talked about fish meal as being a common protein source for some cattle feed and just being as one additional source of iodine in that, I don't know how common of a practice that is.