Aidan:
Hello and welcome to the Ideal Nutrition Podcast. My name is Aidan Muir. I’m here with my co-host, Torwen Eerkens. And this is episode 256, where we’re talking about nutrition for Hashimoto’s. Hashimoto’s is a condition where the body’s own cells attack and damage the thyroid gland. Hypothyroidism is when not enough thyroid hormone is produced. That can happen for a variety of reasons. But, Hashimoto’s is one of the most common ones.
Basically, the immune system mistakenly views thyroid cells as foreign tissue. It produces antibodies to destroy them. And that leads to reduced production of thyroid hormones.
Torwen:
Common symptoms can include weight gain, dry skin, feeling cold, poor memory and fatigue. They can also include sore muscles and joints, depression, and reduced libido. It’s typically diagnosed through your GP initially. They will test for anti-thyroid antibodies, thyroid stimulating hormone, TSH, and thyroxine in the blood.
Aidan:
We’re going to talk mostly about nutrition today. But we are going to start with the medical side. The medical side can be a bit complex. Some people need medication and others do not. For example, if somebody had glaring gaps in their nutrition, that could cause hypothyroidism. Addressing those could help, particularly if they’re borderline as well.
At the other end of the spectrum, I’ve seen many people spend years troubleshooting different nutritional solutions. And they have been suffering from symptoms that medication could have addressed quite simply. The most common medication is levothyroxine. It is converted into the active thyroid hormone, T4. When dosed appropriately, it often helps manage a lot of symptoms of hypothyroidism. But there are still cases where people will get other symptoms as well.
And dosing often needs to be adjusted over time. This helps keep things in a sweet spot type of range.
Torwen:
From a dietary perspective, it is best to take levothyroxine separately from food. Typically, we recommend waiting at least 30 to 60 minutes after food. That is a pretty good strategy.
You could take this medication on an empty stomach in the morning. Aim for at least 30 to 60 minutes before breakfast. This is because a lot of foods can affect the absorption of this medication. This includes things like coffee, calcium and iron.
Aidan:
Talking diet now, there are a lot of individual things we can go through. But I want to start with overall diet. A lot of similar rules in terms of having a good diet still apply. As we go through, we’ll see a lot of nutrients linked with thyroid function. Therefore, having a good nutritional intake in general is a good idea.
Another thing is a general anti-inflammatory style diet. It is kind of in the name to a degree, with Hashimoto’s thyroiditis. The “itis” implies inflammation. You could make a link that doing anything generally anti-inflammatory could potentially help with that.
But beyond that, a general anti-inflammatory style diet is nutrient-rich. Whichever mechanism has the biggest impact, we have evidence of this mattering. There was a 2024 cross-sectional study that I’ve put into the show notes. They used the dietary inflammatory index. And they found closer adherence to an anti-inflammatory diet was associated with better thyroid function markers. This was in people with Hashimoto’s.
Torwen:
Jumping in, we’re going through specific nutrients that can be beneficial. We’ll also cover things that are potentially recommended to avoid or limit. Starting with iodine, the thyroid gland requires iodine to make thyroid hormones. It’s funny because iodine deficiency is not super common in developed countries. That is mainly because we fortify products like salt.
Iodine is important. But it is also a nutrient we do not want to overdo. Because you can consume too much, which can lead to worsening of hypothyroidism.
Aidan:
Another major one is selenium. A lot of selenium in the body is found in the thyroid. That is part of why this matters. Having a suboptimal amount could contribute to the condition. A review found selenium supplementation can decrease symptoms and improve overall wellbeing. The effects were far more noticeable in those who had a deficiency.
I point to this through a specific lens. Sometimes, I’ve heard people say nutrition cannot solve Hashimoto’s. It would be silly to dismiss it to the point that nutrition has no impact. Selenium plays a bit of a role, as do a few other things.
At the other end of the spectrum, I’ve heard people in the alternative nutrition world do similarly dismissive stuff. They act as if selenium is the answer to everything. They’ll say anyone with hypothyroidism just needs selenium and that will solve it. That is obviously extreme as well. The answer is somewhere in between those two.
There are also downsides to over-supplementing. So, if somebody is supplementing, it is usually around 100 to 200 micrograms per day. If they are having it through food, one to two Brazil nuts per day is the sweet spot. You could technically overdo it if you had heaps of Brazil nuts every day.
I don’t know if you saw this, Torwen. But have you seen stuff on inositol and selenium?
Torwen:
Not a lot.
Aidan:
The way I came across this was from an article I wrote on Hashimoto’s. It was in 2019, 2020 or 2021. I don’t know. I think it was actually six years ago when I wrote it.
In preparation for this podcast, part of it was looking at what I had done previously. Obviously, I’m always learning. So I added some stuff in as well. But then I also looked at the biggest breakthroughs over the last six years. What looks to be one of the biggest nutritional breakthroughs is co-supplementing myo-inositol alongside selenium.
So, what people have found in these studies is that TSH levels drop noticeably more when supplementing both together. TSH is thyroid-stimulating hormone. It looks really impressive. It seems to be one of the bigger breakthroughs, doing both of those things.
It’s one of those tricky ones to communicate. It is not fully magic, but it does seem to help in a lot of cases. Myo-inositol is often easy to source and dose.
Torwen:
That makes a lot of sense. Moving on to the next one, something that could interfere with thyroid hormone production is goitrogens. I hope I pronounced that correctly.
Aidan:
Goitrogens, yeah.
Torwen:
Because they inhibit iodine uptake. This is why they are occasionally recommended to avoid. This is especially if someone has low iodine as a contributing factor. That could potentially be why hypothyroidism is an issue for them.
Foods high in goitrogens include broccoli, cauliflower, cabbage and bok choy. It’s a long list, but generally it is mostly those dark leafy greens. Research here is not super clear. But it seems okay to include them in moderate amounts. It does not need to be black and white, where you eliminate them completely.
Aidan:
Yeah, that’s my sense as well. In most cases, I would not even think about it. There are a few rare cases I’ve come across. Actually, only one client in my life was sending it on goitrogens. They were the only vegetables they liked.
It was the first time I had to say we actually needed to scale this back. In their case, we did see some changes in their thyroid markers. It’s hard to say because there were so many moving parts. Was it the goitrogens, or was it other things? But only once have I had to scale that back with somebody.
Another technical goitrogen is soy. But it is also worth talking about in isolation. A lot of people recommend cutting out soy. If you looked up nutrition for Hashimoto’s, you would see people talking about this.
There is a review looking at 14 relevant studies. It found minimal impact on thyroid markers. I think that is really relevant. Often, you see people saying, do this and this will really help. But we have 14 studies looking at it, and it found minimal impact. If there was anything, it cannot be that big.
There are gaps in that review though. For example, a lot of people in those studies were on appropriately dosed medication. That is a huge factor. So I still think there are some cases where it is likely to be more relevant.
Case number one is people with subclinical or borderline hypothyroidism. The potential small impact could matter more. And the second is people with low iodine intake or exceptionally high soy intake. It’s a similar concept. If people are having heaps of it, I would be more cautious.
Torwen:
Yeah, that makes a lot of sense. I read that one as well. And I definitely saw the impact. If medication is dosed accurately, there is probably no need to be black and white. Just be mindful.
Moving on then to gluten. This is one that I think is maybe more spoken about on social media. Most of the time, it is spoken about anecdotally. But there is mixed research on whether gluten impacts thyroid antibodies.
It is important to note that coeliac disease is more prevalent in those with Hashimoto’s. So it makes sense to test for coeliac disease. And make sure testing is done before removing gluten. Then you can see if that helps with symptoms.
Aidan:
Yeah, absolutely. It’s another thing where the research has evolved. It has gotten to the point of an even stronger stance. When I wrote that article in 2019 or 2020, it was pretty much in this position. You should probably test for coeliac disease.
But I was even writing in that article that there is no downside to cutting out gluten. That is if you replace it with other things. I do not think you need to, so on and so forth. But now in 2026, it is clear this has been studied pretty thoroughly.
It does not seem to improve symptoms unless you have coeliac disease. Or potentially, non-coeliac gluten sensitivity. That is a tricky thing to define. But if we looked at statistical identifications of perceived non-coeliac gluten sensitivity, it seems higher in Hashimoto’s. So potentially, it is worth factoring in.
Now, talking about dairy. One thing that stands out to me is lactose intolerance appears more prevalent in Hashimoto’s. Surprisingly, there is still less research on this than I would expect. But one study stands out to me. From memory, there were 83 people in the study. And they found 75% of them had lactose intolerance. That is crazily high.
I would almost always start there with somebody with Hashimoto’s. I would ask whether we should see if they have lactose intolerance. I would start there over looking to completely avoid dairy. Statistically, this appears far more common.
There are once again anecdotal reports of people dropping dairy and feeling better. I would not actively recommend that point. That is particularly with what I perceive as skewed outcomes due to lactose intolerance. But if you dropped dairy and adjusted your diet well, you can still have a great diet. You can still do that without dairy if you wanted to trial it. But I would not say the research is pointing in that direction at this stage.
Torwen:
And how much easier is it to go lactose-free?
Aidan:
It’s so much easier. I don’t know if you have this experience with clients. I do not talk about this much in the first consult. But there are so many people in the first consult who are unsure about lactose intolerance or dairy intolerance.
It is pretty easy for me to pick. I will think, this is lactose intolerance. They also have not taken the next step with learning more about lactose intolerance. I do not want to prioritise it in the first session. But in my head, I’m instantly thinking their life could be so much better. There are so many options.
Torwen:
It is an easy one for us to target.
Aidan:
Yeah. I do not want to go too deep on it. But there are so many easy alternatives for almost every case.
Torwen:
Moving on then to vitamin D. Again, those with Hashimoto’s are more likely to have suboptimal vitamin D levels. This seems to be a common theme through a few things we are talking about today. Those with Hashimoto’s can have suboptimal levels.
We know vitamin D plays a role in lots of bodily functions. The same goes for the thyroid. There is a potential link between vitamin D and reducing TPO and thyroglobulin antibodies. So, as with any other nutrient, it is important to check levels. Then aim to supplement if necessary. Potentially, this could mean going above that minimum safe range.
Aidan:
I’m going to put a few others in that category. I’ll put zinc, magnesium and B12 in these categories as well. I think it is good to have a good intake of them in general. And if you get benefits from a thyroid perspective as well, that is a bonus.
Zinc is required for the production of T3, T4 and TSH. Therefore, avoiding a deficiency makes sense as well. Some research has found that zinc helps with thyroid function. There is not enough research to have a strong take on it. But once again, you should have a good intake anyway. It is beneficial for other reasons.
B12 deficiency is way more prevalent in Hashimoto’s than in the general population. I would say this is actually even more worth being on top of. The easy thing you can do is get a B12 blood test and see. If you are getting that test, you may as well test vitamin D. You may as well test a bunch of other nutrients as well.
Another one we wrote in our planning for this is magnesium. But there was, once again, surprisingly less research on this than I would expect. There are a bunch of reasons why, mechanistically, it could be linked. But there is not much showing that improving low magnesium intake improves markers.
Once again, I think it is a good idea to generally improve that as well. And there are many symptoms associated with Hashimoto’s that could improve through better magnesium intake.
Torwen:
Something we have spoken about on this podcast before is that a lot of people have suboptimal magnesium intake. So even look at dietary intake first. And then supplement if that is necessary.
Iron deficiency is another one that is more common in those with Hashimoto’s. It may partly be due to the prevalence of coeliac disease. It may also relate to reduced absorption in the gut. Iron is required to produce those thyroid hormones. So again, a deficiency reduces that production. Get a blood test, test those levels and supplement as needed.
Aidan:
And the final nutrient before we talk about other aspects is omega-3. It is not one that could mechanistically help. But there is not much human research. Reducing inflammation is the main mechanism that checks out here. And there are a few other ones as well.
It sits in the same category. I think having a decent omega-3 intake would be a good idea. That is even if it is not thyroid-specific. Once again, if you go back through all the nutrients, a good diet covers a lot of them. There is some more targeted stuff, like selenium.
I do not know what percentage of people would have Brazil nuts regularly. So I would be more targeted with some of them. But a good diet in general matters. A blood test to check some of these nutrients matters too.
Torwen:
Cool. Moving on to some other nutrition strategies then. So, we have mentioned a few things, including lactose and potentially non-coeliac gluten sensitivity. These have a role in the digestive system.
Something we talk less about with thyroid hormones is that they do play a role in digestion. So, Hashimoto’s can be associated with slower motility. This can cause issues like constipation.
Making sure we do constipation management where possible may help. This might include aiming for a pretty high-fibre diet. Or increasing fibre slowly. It might also include considering soluble fibre supplementation with things like psyllium husk. Adding specific fruits like kiwifruit can also help move things through.
Aidan:
Absolutely. It is the same concepts we would normally use for constipation. But it becomes so much more important because that symptom is more common.
The whole idea of certain functions in the body being downregulated due to hypothyroidism extends elsewhere. It extends to a lot of other functions in the body. This leads to the next topic, which is weight management.
Due to these functions being downregulated, energy expenditure can be a little bit low. This is particularly if thyroid hormones are not being managed through medication.
There are two things I would point to. Thing number one is that downregulation means the body spends fewer calories on these processes. And thing number two is living with these symptoms makes it harder to be active. So that is another factor.
With unmedicated Hashimoto’s in research, reductions in resting metabolic rate typically extend to 15%. I point to that through the lens of two things. One, there is a reduction, and that is very clear. It is something that exists.
Two, I like to point to how big the reduction is. Without pointing to a number like 15%, it is hard to quantify. In many cases, people can see it in black and white. They might think hypothyroidism makes it incredibly difficult to lose weight. Whereas with 15%, it is a hurdle, but it is not impossible.
The second part is that we ideally manage the medication side of things. Or we manage anything else to get the hormones back to a normal point. From an energy expenditure perspective, research shows this can make a difference.
Once hormones are back to a good level, most people’s energy expenditure comes within a couple of percent. That is compared to what you would expect. It is actually a little bit under on average. And my speculation as to why relates to symptoms. If somebody has gone through a medical journey, they might have less muscle mass on average. They might have been doing slightly less exercise, and so on. That would explain the small difference in RMR.
Once you get back to normal hormonal function, things are pretty close to normal. In that case, from a weight management perspective, we do similar things to usual. We factor in that, in some cases, there is a bit of a reduction. Then we are also conscious of symptom management. In general, we look for ways that could make this easier too.
Torwen:
And this is something that I think we probably see and manage in practice fairly often. Off the top of my head, I had a hypothyroidism client who went in for an RMR test. It actually came out slightly higher than 15% lower than the predicted amount. With time, as we work through things, hopefully that number can change a little bit. Regardless, we work with a calorie deficit. Then we adjust that number based on the results we are seeing.
The last little one I want to add is gut health. Thyroid diseases are frequently associated with things like dysbiosis. This may encourage further inflammation. So it makes a lot of sense to focus on general gut health as well.
Aidan:
Good addition. I like that. We were both reading the same paper earlier today. There was a big section on that as well.
Torwen:
Amazing. Should we wrap up here then?
Aidan:
Sounds good. This has been episode 256 of the Ideal Nutrition Podcast. As always, if you have enjoyed listening, please leave a rating and review. We would massively appreciate it.