Latest / Common Sense Health / Why Your Thyroid Stops Working When You Get Too Much Iodine
Transcript
- Stephen: It's a very hot day in the UK. Anyway, hello. Your thyroid is a bit like a careful chef in a busy kitchen. This chef just needs the right amount of iodine to whip up its signature hormones. But if you suddenly tip half a sack of iodine into the mixing bowl, the chef's operation doesn't speed up. The chef simply stops and waits for the mess to clear. Now that pause button, that pause is known as the Wolf Chaykoff effect. Not heard of it before, you? Anyway, before we dive into the details, a quick thyroid 101. The thyroid sits at the front of your neck like a small butterfly shaped gland. Its main job is to produce two key hormones, thyroxine, which is T4, and the more active triiodothyrene, which is T3. And these hormones act as the body's accelerator pedal, controlling how fast your cells burn fuel, how warm you feel, even how your heart beats. And without them, everything just slows down. And with too much, things race. The gland takes iodine from the blood, combines it with an amino acid called tyrosine and packages the result into usable hormones. Simple in principle, but the system is exquisitely sensitive to sudden changes in the supply. And so back to the Wolff-Chakoff effect. When iodine intake jumps dramatically, the thyroid grabs far more than it can immediately use. Now this excess iodide builds up inside the gland and blocks the next step in the process. something called organification. In plain terms, organification is the chemical step where iodine is properly attached to tyrosine to form the actual thyroid hormones. With too much iodide floating around, that attachment actually gets temporarily switched off. It is the gland's built-in safety mechanism to avoid tipping into overdrive. Now, here's where things get a little bit more fascinating. If you scroll through your social media, you'll find influences. is telling you that 50 milligrams isn't enough of iodine, you need 75 and then maybe 100. Then someone chimes in that they take 150 milligrams and they feel amazing. The logic seems straightforward. Iodine makes thyroid hormones, so more iodine must make more thyroid hormones. ⁓ Except that's not how the body actually works. It's a bit like being told that if you add more petrol to a flooded engine, it will run better. The opposite is actually true. Your thyroid has a feedback loop designed precisely to stop this from happening. And when you flood it with iodine, you can trip that circuit breaker. The result? You feel worse. Your tests look confusing and you blame yourself for not being strict enough when actually you need to do the exact opposite of what the internet has told you. Hmm. Absolutely. The real kick in the teeth is that people are spending their hard earned cash on increasingly expensive supplement regimes, convinced that the next dose will be the one that finally works. Meanwhile, the answer is often to take less. That's right, less. A holiday from the iodine, or a sensible reduction in dose. And that might accomplish more than any those fancy tinctures or high dose capsules. The irony of the influencers pushing people towards more expensive regimes when the fix is effectively free is enough to make you want to scream into a pillow. There are people right now who are doing everything right. Eating well, supplementing like it's their duty and following every protocol, yet still feeling exhausted or brain fogged and wondering why on is wrong with them? And the answer might not be adding anything at all. It might be taking a step back, just having a breath and giving the thyroid a chance to remember what normal looks like. Now, the original work by Wolff and Chekhov was done in rats in the 1940s, but the effect has been observed in humans too. Studies involving people given large doses of iodine through contrast dyes for x-rays or through medications have shown the same temporary shutdown of hormone production. One particular instructive example comes from patients receiving potassium iodide therapy for asthma or other respiratory conditions. in the mid 20th century. Clinicians noted drops in T4 and rises in TSH shortly after the high dose initiation, followed by a return to baseline once the gland escaped the inhibition. Similar patterns are documented in the literature around radioactive iodine uptake tests where pre-treatment with high dose iodine measurably suppresses uptake for days afterwards. And reviews in journals like thyroid and endocrine reviews describe how most healthy eventually escape the block after a few days to weeks as the cells down regulate their iodine uptake. In people with pre-existing thyroid issues, however, that pause can linger even longer. Now blood test numbers add another twist. TSH, thyroid stimulating hormone, 3T4 and 3T3 are all measured as concentrations, nanograms or picograms per deciliter of blood. Drink a couple of extra glasses of water and the volume of your blood slightly changes, which can nudge the those numbers a little bit. The same happens if you're mildly dehydrated. And that is why single readings are never the whole story. Interpreting bloods in the context of a carnivore, ketivore or ketogenic way of eating is pretty crucial. On low carb especially, your body needs less T3 because there is less glycolysis happening. The T3 pyruvate connection means that when carbohydrate intake drops, demand for the active hormone falls naturally. A reading that can look low on paper can be entirely appropriate rather than a signal to push iodine even higher. So what about the person who has been taking 60mg of iodine daily, found it stopped working and has now moved to 90mg in the hope of fixing their thyroid? Well the practical takeaway is that the higher dose may actually be extending the wolf take-off break, rather than releasing it. The sensible next step is usually to reduce the dose, take a break, or least run some proper testing that includes reverse T3 and a urinary iodine measurement. Cystatin C is also worth considering alongside the EGFR for kidney context if that's relevant. So we want the joined up thinking which beats simply adding more iodine every single time. Now in the end your thyroid is a precision instrument not a bucket you need to keep topping up. Give it the right amount in the right setting and it will usually get on with the job without needing you to play the amateur chemist. Sometimes the smartest thing you can do is is nothing and pocket the savings while you're at it. So until next time, keep the steak on the plate and the iodine in the sensible range and your thyroid will actually thank you. Hope you enjoyed this and if you did, please consider liking, sharing and subscribing. ⁓ there be a graphic so imagine you got cell and got three iodine ⁓ and then you've got ⁓ three iodine molecules coming in, okay? And that's okay, that goes through the system and you make some thyroid hormone. If you suddenly double the amount of iodine coming in, but you've got the same amount of receptors, you're flooding those receptors. That's how simple this is. So those receptors will go, well, there's a bit too much, are we going to down-regulate or are gonna shut down for a bit? It really is that simple. So mega-dosing or high-dosing isn't as simple as it seems. And it might be working initially, but then over the long term, advise people who come to me with thyroid issues have been having thyroid issues for a long, time. Anyway, hopefully that's helpful. Do consider liking, sharing and subscribing, as I say, easy for me to say. And if you haven't liked it, why not drop a comment to tell me why you haven't. And I'll see if I can do better next time. Thanks very much for listening.