Episode 65: AIP for Hashimoto’s – The Polish Study on Nutrient Density, Symptoms & Thyroid Health

What happens when researchers outside the AIP community independently decide to study the Autoimmune Protocol in an academic setting? In this episode, Mickey breaks down a 2023 research trial from Poland that evaluated AIP for people with Hashimoto’s thyroiditis who were euthyroid on paper—but still highly symptomatic.

As part of the AIP Medical Research Review Series, this episode explores the second published clinical study on AIP for Hashimoto’s. The Polish research team examined not only symptoms and thyroid labs, but also nutrient intake, body composition, and thyroid ultrasound findings—adding new layers of insight beyond earlier research.

This episode walks through how the study was designed, what changed after 12 weeks on AIP, and how the results compare to the Abbott pilot trial. The findings offer compelling evidence that nutrient density, inflammation reduction, and symptom improvement can occur even when thyroid labs remain within normal ranges.

In this episode, you’ll learn:

1. Why Polish researchers decided to study AIP after the Abbott trial
2. Who participated in the study and how the AIP intervention was structured
3. How nutrient density changed without calorie restriction
4. What happened to thyroid hormones, antibodies, and thyroid gland volume
5. How body weight and body fat shifted over 12 weeks
6. Which Hashimoto’s symptoms improved most significantly
7. Why symptom relief often matters more than antibody changes
8. What this study adds to the growing body of AIP research

References

Abbott, R. D., Sadowski, A., & Alt, A. G. (2019). Efficacy of the Autoimmune Protocol Diet as Part of a Multidisciplinary, Supported Lifestyle Intervention for Hashimoto’s Thyroiditis. Cureus, 11(4), e4556.

Krysiak, R., Kowalcze, K., Okopień, B., & Gdula-Dymek, A. (2023). Effects of an Autoimmune Protocol (AIP) Diet on Changes in Thyroid Parameters in Hashimoto’s Disease. Nutrients, 15(9), 2101.

Resources:

1. AIP Foundation Series – Free 5-day email course with printable food lists, beginner resources, and updates on new AIP research
2. The New Autoimmune Protocol (Preorder) – Mickey Trescott’s upcoming book translating the latest AIP science into a practical, modern guide

Episode Timeline:

00:00 – Introduction & why this Polish study matters

02:16 – Study overview and research goals

03:54 – Hashimoto’s refresher: euthyroid but symptomatic

05:05 – Key questions the researchers wanted to answer

06:23 – Participant profile and exclusion criteria

07:23 – AIP intervention design and duration

10:15 – Clinical measures and nutritional analysis

13:11 – Nutrient density results

15:54 – Thyroid hormones, antibodies & ultrasound findings

18:15 – Body weight and body composition changes

20:11 – Symptom improvement results

22:13 – Nutrient–thyroid marker relationships

23:23 – Interpreting hormone and antibody shifts

25:53 – Comparing results to the Abbott study

29:54 – Practical takeaways for listeners

33:06 – Recap, resources & wrap-up

In our last Hashimoto's research episode, we talked about a study

that was very close to home for me, the Abbott trial, a community-funded

project that Angie and I helped bring to life alongside Dr. Rob Abbott.

That study showed that a structured AIP diet and lifestyle intervention

could significantly improve symptoms, quality of life and inflammation

in women with Hashimoto's who are technically euthyroid on paper.

Today's study is just as exciting for a different reason.

A research team in Poland read about the Abbott trial, looked at

the publicly-available information on AIP, and decided to design their

own clinical study to test it: independently, in their own academic

setting, and with their own patients.

They took the concept of AIP, translated it into their clinical

context, and honestly, they did a really incredible job.

And not only that, but the study was about twice as large in terms of

participants and it added several layers that we didn't see in the Abbott paper.

In addition to the symptoms and thyroid markers, the Polish team

looked at nutrient density, so how people's vitamin, mineral and

macronutrient intake changed on AIP.

Their body composition, so they looked at shifts in body weight and body fat.

And then also thyroid ultrasound, which gave them a glimpse into

changes in the thyroid gland itself.

And of course, they still looked at those thyroid hormones and antibodies, plus the

symptom changes and overall wellbeing.

So in a lot of ways this study acts like a companion to the Abbott trial.

Same general idea, meaning AIP for Hashimoto's in euthyroid patients,

but with a different research team in a different country, and

using a slightly different design and a richer set of measurements.

It's a glimpse into what happens when AIP starts to be tested by outside

researchers who simply find it interesting and potentially helpful.

Welcome back to the Autoimmune Wellness Podcast.

I'm your host, Mickey Trescott, and this is another episode in our AIP

Medical Research Review series where I walk you through the published clinical

studies on the Autoimmune Protocol: what they examined, what they found,

and what it all means for people living with autoimmune disease right now.

Today we're diving into a Polish study that evaluated AIP for Hashimoto's

thyroiditis in an academic setting.

We're going to look at who participated, how the AIP intervention was structured,

what changed in terms of symptoms, thyroid hormones, antibodies, thyroid ultrasound

findings, body composition and nutrient intake, and how these results compare

to what we saw in the Abbott trial.

As always, this podcast is for educational and informational purposes only and

is not intended as medical advice.

Be sure to talk to your healthcare provider before making any

changes to your treatment plan.

In today's episode, we're exploring the second clinical study published

on the Autoimmune Protocol for Hashimoto's thyroiditis.

The name of the paper is Effects of an Autoimmune Protocol AIP Diet

on Changes in Thyroid Parameters in Hashimoto's Disease, published in 2023.

If you'd like to read along, I've included a direct link to the

open-access study in the show notes.

We're going to walk through the full study design: who participated, how the

AIP intervention was implemented in this academic setting, and the broad range of

outcomes that the researchers measured.

Then we'll break down the results, including shifts in symptoms, thyroid

hormone levels, antibody patterns, nutrient density, body composition, and

even those thyroid ultrasound findings.

By the end of the episode, you'll have a clear understanding of what this

research team discovered, how the results compare to the Abbott trial, and why

the study represents an exciting next step in the growing global interest

in AIP for autoimmune thyroid disease.

Before we jump into the study, here's a very quick refresher on Hashimoto's

and why this research is important.

Hashimoto's is an autoimmune condition where the immune system attacks the

thyroid gland, thyroid hormone levels, things like TSH, free T4, free T3 can

remain normal for years, even while the autoimmune process is still active,

diagnosis often includes thyroid antibodies like TPO and Tg, which confirm

that the immune system is involved.

The challenge is that many people with Hashimoto's continue to feel

unwell, even when their labs look fine.

So they will have symptoms like fatigue, brain fog, digestive issues,

mood changes, and weight fluctuations, and very commonly these are not

explained by hormone levels alone.

And this is the group that both the Abbott study and these

Polish researchers focused on.

People who were medically stable on paper, but still dealing

with significant symptoms.

So with that quick refresher, let's talk about why the Polish team wanted to

study AIP, and how their approach adds something new to what we already know.

After the Abbott study was published, it sparked interest well beyond

the AIP community, including this dietitian led research team in Poland.

They saw the promising improvements in symptoms and quality of life and

wanted to explore AIP further, but with a slightly different focus.

Here's what they wanted to know.

First, what AIP support wellbeing without disrupting those thyroid hormones?

The Abbott trial showed stable thyroid labs, but the group was pretty small.

The Polish team wanted to test this in a larger cohort of also euthyroid patients.

Second, the researchers wanted to understand whether AIP was associated

with physical changes in the body itself, particularly in the thyroid

gland and overall body composition.

To explore this, they added thyroid ultrasound imaging to assess changes

in thyroid volume, along with the standard anthropometric measurements to

see how physiology shifted over time.

And lastly, how does AIP change nutrient intake?

They suspected that increases in nutrient density might be

one mechanism of improvement.

So they performed detailed dietary analysis.

In other words, the Polish team wasn't repeating the Abbott trial.

They were expanding it, asking new questions about thyroid structure,

nutrient density, and how AIP performs in a more traditional medical setting.

With that background, let's take a look at who actually participated

in this Polish Hashimoto study.

This trial enrolled 28 adults with Hashimoto's thyroiditis.

As is very common with this condition, the vast majority were women, 27

women, and one man with an average age of 35 years, ranging from 23 to 55.

And importantly, the researchers excluded anyone who had used an

elimination diet in the past year.

This means that participants were approaching AIP as a new intervention,

similar to the design of the Abbott study.

People were also excluded if they were pregnant or breastfeeding, had celiac

disease, severe chronic illness such as renal or liver failure, malnutrition,

eating disorders, or had implanted medical devices like electro stimulators.

So taken together, this group represents a very common clinical

picture in Hashimoto's: working-age adults, mostly women, medically

stable, not new to the disease, and still seeking ways to feel better.

Next, let's look at how the Polish research team structured their AIP

intervention, because this tells us a lot about how participants

actually implemented the protocol and how closely it aligns with the

version of AIP used in other studies.

This was a 12 week dietary intervention guided by a dietitian, and based on

the core principles of the Autoimmune Protocol Elimination Phase, as originally

outlined by Dr. Sarah Ballantyne.

The focus here was on nutrient density, whole foods, and avoiding

ingredients that may contribute to immune dysregulation, gut irritation,

or disruption of the gut microbiota.

The Polish team removed the same food groups that we exclude in Core AIP: eggs,

dairy, cereals, grains, nightshades, legumes, food additives and highly

processed foods, food containing lectins, which is their terminology, I think that

originates, way back in AIP's history.

We don't really use that anymore, but this captures the broad AIP elimination pattern

in a slightly simplified academic format.

Participants were also encouraged to eat foods that support the

microbiome, the intestinal mucosa and overall nutrient density.

Their individualized AIP plans emphasized a variety of whole, unprocessed foods,

fermented foods, and foods described as live, such as pickled or naturally

cultured, foods free from heavy processing or high heat industrial

preparation, gluten-free flours when needed, such as coconut and arrowroot.

And while this paper doesn't detail every addition the way that the

Abbott study did, the overall emphasis aligns with AIP fundamentals: whole

foods, nutrient density, gut support, and avoidance of these extra things

that we know can be problematic for people with autoimmune disease.

So next let's talk about how the diet was delivered.

Unlike the Abbott trial, which included coaching, group support

and a staged six week transition, the Polish study used a 12 week

Elimination Phase guided by a dietitian.

So there was no phased transition described.

Participants followed their individualized AIP menu from the start.

So this is a much longer timeframe in elimination, this is three

months, versus one month.

And the paper notes that each participant received a written list of excluded and

allowed foods, an example menu, and then in an individualized AIP plan that was

developed by the research dietitian.

So this intervention was a little less lifestyle focused and more

strictly nutritional and only focused on the Elimination Phase, but for

far longer than the prior studies.

So again, that 12 weeks versus the five and four from the

IBD and Hashimoto's trials.

Now to understand what changed during the 12 week AIP intervention, the Polish

research team used a comprehensive set of assessments including thyroid labs,

the ultrasound, body composition markers, nutrient intake, and symptom tracking.

These measures help us understand both how people felt and what

was happening physiologically.

First, they completed thyroid hormone and antibody testing, so before and

after they completed a full thyroid panel including: TSH, total T3 and T4,

free T3 and T4 anti-thyroglobulin and anti-thyroid peroxidase antibodies.

These markers allowed the researchers to monitor thyroid function and

autoimmune activity throughout the study.

Next, a unique aspect of this trial was the inclusion of

thyroid ultrasound imaging.

Clinicians measured the size of both thyroid lobes and the structural

appearance of the thyroid gland.

Ultrasound is commonly used in Hashimoto's to evaluate the degree of

inflammation and long-term tissue changes.

So this added an important structural dimension to the research.

Participants also underwent body measurements before

and after the intervention.

They took their weight, their BMI, their body fat and muscle mass via bioelectrical

impedance, their height, and these assessments in the clinic allowed the

researchers to evaluate changes in weight, fat mass, and overall metabolic health.

Another distinctive feature of this study was the detailed

analysis of nutrient intake.

Before beginning AIP participants completed a three day food record

to document their usual diet.

The research team calculated their calorie intake, their macronutrients, their

fiber, and their micronutrient intake.

And then using these data the dietitian created individualized AIP

menus tailored to each participant's energy needs, calculated using

the Harris-Benedict equation and their physical activity levels.

And then they also used the Polish Nutrient Intake Standards.

Participants continued any supplements or medications.

The AIP menu itself was nutritionally balanced, so the the researchers did not

recommend any supplements to be added.

For symptom tracking participants also rated their subjective wellbeing

by reporting on symptoms commonly associated with Hashimoto's, such

fatigue, digestive symptoms, mood issues, cognitive changes, skin and

hair changes, muscle and joint pain.

These reports were collected before and after the intervention to assess

how people felt alongside all of those lab work and the ultrasound results.

And then adherence to the intervention was supported through remote contact

with the dietitian, monthly online check-ins, ongoing menu review and

adjustment, and this allowed the researchers to monitor compliance

without requiring in-person visits.

Okay, so now the fun part, onto the results.

We'll begin by discussing nutrient density.

One of the most exciting parts of this Polish study is how clearly it showed

the nutritional shift that happens when somebody moves from a standard

diet to the Autoimmune Protocol.

And this is something that we often talk about in theory, but here

we get to see it measured as this was a new feature of this study.

So even though the total calories stayed almost identical from before and after

AIP, the average went from 2,067 calories to 1,997 calories per day, the balance of

macronutrients changed in meaningful ways.

Protein increased from 16% to 24% of calories, fat decreased from 33% to

30%, and carbohydrates stayed almost the same, shifting only from 45% to 44%.

So this combination-- higher protein, modestly lower in fat, and stable

in carbohydrates --reflects what we see when people increase whole

foods like vegetables, roots, fruits, seafood, and high quality

meats and reduce processed foods.

But the most striking changes weren't in the macronutrients.

They were in the micronutrients, and this is where AIP really shines.

The study found major increases in nearly every vitamin, mineral

and antioxidant measured.

Compared to the participant's baseline diets, AIP led to: a five times increase

in betacarotene, which is a precursor to vitamin A, a 50% increase in dietary

fiber, a three times increase in vitamin A and a nine times increase

in vitamin C. And then also they found significant increases in a very long

list of essential nutrients, including things like folate, potassium, magnesium,

iron, B vitamins, omega-3 fatty acids and antioxidant rich plant compounds.

So if you are reading along with a study, definitely take a look at

table 2A for all of those nutrient categories and exact values.

So this confirms something we've known for years.

AIP is incredibly nutrient dense.

And a reminder, these participants were not eating

less, they were not eating more.

They were eating the same number of calories.

They weren't relying on supplements.

They were just eating a true, whole food, anti-inflammatory diet, and

their nutrient intake skyrocketed.

This matters because many symptoms in Hashimoto's: fatigue, mood

issues, hair and skin changes, digestive complaints can be heavily

influenced by micronutrient status.

Now let's look at what happened to thyroid hormones, thyroid

antibodies, and thyroid gland volume over that 12 week intervention.

These are core markers for Hashimoto's, and they help us understand how

the body responds physiologically to the AIP dietary pattern.

So all of these participants began the study euthyroid with thyroid hormone

levels already in the normal range.

After 12 weeks of AIP, the TSH decreased by 27% from 3.72 to 2.69.

Free t3 decreased by 13%, free t4 decreased by 11%.

Now, I will note here that even though these participants were classified as

euthyroid, the standard reference ranges for TSH are controversial, especially

in the functional medicine community.

So most providers now consider a TSH of three to be problematic, and

many narrow that window down to 2.5.

So by functional medicine standards, I actually think that these patients could

have been categorized as subclinical or mildly hypothyroid, and seeing them

come back down closer to that 2.5 cutoff is actually a really great result.

And then importantly, even though those free thyroid levels decreased marginally.

All of these values remained within that standard reference range, which

means that the thyroid function stayed mostly stable overall.

These small decreases occurred without pushing anyone towards hypothyroidism.

Now, the antibody results were mixed, and they did see an increase in anti TPO

and a decrease in anti-thyroglobulin, and both of these changes were not

statistically significant, but they are very interesting and we will

discuss them a little bit later.

And then one of the most interesting additions in this Polish study was

thyroid ultrasound, which allowed researchers to measure changes in

the size of the thyroid itself.

So after 12 weeks of AIP, the right thyroid lobe volume decreased

by 5.3%, and the left thyroid lobe volume decreased by 6.2%.

A reduction in the thyroid volume can reflect decreased inflammation or

reduced immune activity within the gland.

Another key area the Polish research team examined was how body weight

and body composition changed over the 12 week AIP intervention.

These measurements offer insight into metabolic shifts, inflammation, and

overall health trends during the study.

The results were statistically significant across every measure.

So first, body weight and BMI decreased.

After 12 weeks on AIP body weight decreased by 4.83%, so that's about

roughly eight pounds on average.

BMI decreased by 5%, which brought a lot of these participants closer

to the normal range for BMI, even though this intervention was not

designed as a weight loss program.

Body fat percentage decreased by almost 10%.

Nearly a 10% reduction in body fat over 12 weeks is substantial, especially

without intentional calorie restriction.

This suggests improvements in metabolic efficiency, inflammation,

and overall diet quality.

Now, body muscle percentage did decrease by 4% and this decrease

appears to be relative to overall fat loss and total weight reduction,

rather than a true drop in lean mass.

So how do we piece all of this together?

I think that even though the AIP diet was not designed as a weight loss

intervention, participants experienced meaningful improvements in their

body weight, their body mass index, their body fat percentage, and these

are things that are all a primary concern for patients with Hashimotos.

All of the changes were statistically significant and reflect the shift

towards a more nutrient dense, less inflammatory, whole food dietary pattern.

And importantly, these findings occurring alongside stable thyroid

hormone levels suggest that there's something about the diet that is

supporting metabolic improvements without negatively impacting thyroid function.

The Polish research team also examined changes in daily symptoms, not with a

validated tool like the Short Form 36 or the MSQ, but through a simple checklist

of common Hashimoto's-related symptoms.

Participants indicated whether they were experiencing each symptom before beginning

AIP, and then again after the 12 weeks.

While this approach isn't standardized, it does give us a helpful snapshot of

how people felt during the intervention.

At baseline, many participants were dealing with a wide range

of classic Hashimoto symptoms.

The most frequent were: 82% experiencing tiredness, 71% experiencing dry

skin, 71% experiencing brain fog, 64% experiencing drowsiness, 64% experiencing

hair loss, and 61% experiencing intestinal gas and flatulence.

So these numbers reflect what we commonly hear from people with Hashimoto's who

are technically euthyroid, but still have all of these symptoms, right?

And after the intervention, the percentage of participants reporting many of

these symptoms decreased dramatically.

Some of the biggest changes included that tiredness going from 82 to 29%,

impaired concentration from 71 to 18%, which I think is just amazing.

Flatulence from 61 to 29%, gas, 61 to 21%, fatigue from 50 to 11%, dry

skin from 71 to 32%, hair loss from 64 to 32%, joint pain from 57 to

21%, weight gain from 57 to 11%, and then muscle cramps from 43 to 7%.

And this trend is unmistakable, the majority of participants felt

noticeably better after 12 weeks on AIP.

They experienced improvements in energy, cognition, digestion, skin and

hair, joint pain, and overall sense of wellbeing, all while maintaining

those stable thyroid hormone levels.

So next on note on thyroid-nutrient marker relationships.

The Polish research team also explored whether changes in specific

nutrient intake were linked to changes in thyroid hormones, antibodies,

or thyroid ultrasound findings.

This analysis was very exploratory, but it produced some interesting points.

For example, they found that increases in manganese intake were

associated with decreases in TSH.

Vitamin D, iodine, vitamin C, folate, and even caffeine intake were

all linked to changes in free T3.

Long chain omega-3 and omega-6 fatty acids were the strongest

predictors of changes in free T4.

And surprisingly retinol, which is vitamin A and the amino acid isoleucine, were

tied to shifts in anti TPO antibodies.

Now it's important to note that these models don't prove cause and effect, but

they highlight just how nutritionally sensitive thyroid physiology may be.

And if you're curious about the full list of nutrient relationships or you

want to see the detailed equations, you can find all of it in the tables

and supplementary materials of the published paper linked in the show notes.

Now that we've reviewed all of the data, let's take a moment to

unpack what the thyroid hormone and antibody changes might mean.

Because this is an area where Hashimoto's patients and clinicians

often have a lot of questions.

In this study, TSH, free T3, and free T4 all decreased modestly

over the 12 week AIP intervention.

Importantly, all of the hormone levels remained fully within the conventional

reference ranges with a side note that by functional medicine standards, the

mean of this group was actually outside what is considered a good TSH before the

study, but that came back into the normal range by the end of the intervention.

And that's just my analysis.

This mirrors what we saw in the Abbott study: AIP didn't disrupt

thyroid function and hormone levels stayed stable and healthy.

When hormones move slightly within the normal range without crossing any of

those thresholds, it generally reflects natural day-to-day physiological

variation, especially when body weight decreases as it did here.

Weight loss alone is known to shift thyroid hormones modestly downward,

even in people without thyroid disease.

So those antibody results were a little more complex.

Again, neither of these changes reached statistical significance,

but the increase in TPO naturally raises eyebrows, and I think it's

important to interpret in this context.

Antibodies can fluctuate a lot naturally and sometimes very dramatically.

Short term studies commonly show swings in both directions,

even without any intervention.

And it is my feeling that antibodies do not reliably correlate with symptoms.

This is still a very open question in Hashimoto's research.

It is clear that Hashimoto's patients can feel terrible sometimes with

low antibodies, and sometimes we can feel really great with high ones.

In both the Abbott and this Polish study, participants experienced major

improvements in their symptom burden, regardless of their antibody levels, which

I think is a very key point to hone in on.

So when we put these findings together with the Abbott study, one message

quality of life, symptom improvement, and overall metabolic

health are often much more meaningful indicators of progress than those

short term changes in antibody levels.

This aligns very much with what clinicians and AIP Certified Coaches

regularly see in practice and what many patients report experiencing themselves.

Now that we've reviewed the findings, let's look at how this Polish study fits

alongside the Abbott Pilot trial, the first ever AIP study for Hashimoto's, and

what we can learn by comparing the two.

Across both studies, a consistent pattern emerges.

First symptom improvement happens even when thyroid hormone levels are normal.

Both studies enrolled participants who were euthyroid at baseline, meaning

their thyroid hormones were already within those standard reference ranges,

and yet, in both studies, participants reported significant improvements

in symptoms and overall wellbeing.

This mirrors what many practitioners in the AIP Certified Coach community

report in real world practice.

Clients with Hashimoto's often feel dramatically better when

nutrient density increases and inflammatory triggers are removed.

Even when their labs haven't budged.

This reinforces a key message for Hashimoto's care: symptoms

and lived experience can improve significantly independent of

those thyroid hormone levels.

Number two, AIP appears safe and well tolerated across different settings.

Neither study reported serious adverse effects and both

demonstrated strong adherence.

However, adherence was higher in the Abbott study, likely due to the

multidisciplinary support model, which included that weekly coaching, group

community support, structured education, and close practitioner contact.

By contrast, the Polish study used a more traditional dietitian guided

model with remote check-ins and still achieved meaningful improvements.

This suggests that AIP can be successful and both high support and standard

clinical environments, although more support may lead to greater consistency.

Three, both studies point to nutrient density as a key driver of improvement.

The Abbott study emphasized nutrient dense eating, but did

not measure micronutrient intake.

The Polish study did, and the increases were absolutely striking.

Together these studies strengthen the hypothesis that nutrient density,

not just eliminations, plays a central role in symptom improvement

for people with Hashimoto's.

Number four, antibody findings differed and should be interpreted with caution.

The Abbott study showed a small, non-significant

downward trend in antibodies.

The Polish study showed a non-significant increase in one

and a decrease in the other.

It's important to be measured here.

Antibodies can naturally fluctuate.

They don't consistently correlate with symptom burden.

And so those short-term changes up or down are not reliable indicators

of long-term autoimmune activity.

So I think that these two studies together reinforce that antibody levels shouldn't

be the primary measure of whether someone with Hashimoto's is improving using AIP.

Number five, the Polish study contributes something new: objective,

structural and metabolic changes.

This study uniquely included the thyroid ultrasound showing a 5 to 6% reduction

in thyroid gland volume over 12 weeks, and unlike symptom reports, ultrasound

is a non subjective indicator, suggesting that something physical shifted inside

the thyroid gland itself, potentially reflecting that reduced inflammation.

In addition, participants lost about eight pounds on average, they reduced

their body fat by nearly 10%, despite eating roughly the same number of

calories that they were before.

And at the same time, those thyroid hormones remained stable

and within the normal range.

So these changes-- stable hormones, reduce thyroid gland volume, improvements

in weight and body composition-- point to a broader metabolic and

inflammatory benefit that aligns with what many people report subjectively.

Together these two studies paint a cohesive picture that AIP might

offer a meaningful support for people with Hashimoto's who feel unwell

despite those normal looking labs.

And this has now been demonstrated in two independent clinical settings.

What does all of this mean if you are considering using AIP to support

your Hashimoto's symptoms today?

Across the Abbott study and this newer Polish study, several themes emerge.

Number one, make sure to give yourself enough time.

Four to 12 weeks is a meaningful window.

In the Abbott study, participants saw improvements within four to 10 weeks.

In the Polish study, the intervention lasted 12 weeks with significant benefits.

Together, these support the current guidance that a one to three month

Elimination Phase is a solid starting point for many people with Hashimoto's.

Number two, your best indicators of progress are going to be

symptoms and quality of life.

Both studies showed improvements in fatigue, brain fog, digestion,

skin and hair symptoms, mood and overall daily functioning.

And importantly, these improvements happened even when

thyroid labs did not shift.

So pay attention to how you feel, your energy, clarity,

sleep, digestion, and mood.

Those day-to-day changes tell you far more than a lab value

does in those early weeks.

Number three, don't worry about those antibody levels after diagnosis.

Antibodies fluctuate naturally, don't correlate reliably with symptoms,

don't predict how you'll feel, and don't change much in the short term.

So if you're feeling better, sleeping better, thinking more clearly, and

living with fewer symptoms, that is real progress even if your antibody levels stay

the same or temporarily tick up a bit.

Number four, nutrient density is not optional, it is essential.

Both studies emphasized nutrient-dense eating and the Polish study quantified it.

This reinforces a core AIP principle: what you add is just

as important as what you remove.

Loading your diet with vegetables, fruits, quality proteins, seafood, organ meats,

roots, herbs, spices, and fermented foods is one of the most powerful

parts of AIP and likely a big reason that some people feel so much better.

Number five, safe weight loss and body composition changes can happen

naturally without restricting calories or doing a weight loss diet.

Participants in the Polish study ate roughly the same amount of calories,

lost an average of eight pounds, and reduced body fat by nearly 10%.

This supports what we teach in AIP: you don't need to do AIP for

weight loss, you don't need to restrict calories during elimination.

When nutrient density goes up and inflammation goes down, the

body often finds a healthier metabolic balance on its own.

Number six, inflammation can improve even when thyroid labs do not.

Both studies included objective measures that captured inflammatory change.

Hs-CRP decreased in the Abbott study and thyroid gland volume decreased

on ultrasound in the Polish study.

These are physical, measurable indicators that something real is

shifting in the body, even when that TSH, T4 and T3 remain the same.

This is reassuring for anyone who feels better on AIP but doesn't

see proof in their thyroid labs.

AIP provides a structured, nutrient dense, anti-inflammatory framework that

has now been shown in two independent clinical studies to meaningfully

support people with Hashimoto's.

So let's quickly recap what we covered today.

We talked about who was studied: 28 adults with Hashimoto's, all medically

euthyroid, yet still experiencing symptoms that so many Hashimoto's

patients know well-- fatigue, brain fog, digestive issues, skin changes, and more.

We reviewed what changed: after 12 weeks on AIP, participants saw

clear improvements in their daily symptoms and overall wellbeing.

They experienced healthy weight loss and nearly 10% reduction in body fat even

without lowering their caloric intake.

Thyroid hormones stayed stable, and ultrasound showed a 5 to 6% reduction

in thyroid gland volume, suggesting a physical reduction in inflammation.

And we explored why it matters: these results align closely with

the Abbott study, showing that AIP is safe, feasible, and genuinely

helpful for people with Hashimoto's.

Improvements in symptoms, mood, digestion, and energy can happen

regardless of changes in thyroid labs or antibodies and nutrient

density appears to play a major role.

Thank you so much for listening, if you enjoyed this episode, please

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And if you are feeling inspired by the research we explored today, I think you

will really appreciate my upcoming book.

It's called The New Autoimmune Protocol, and it is arriving in May.

It distills all of the latest science into a clear, practical guide,

complete with new recipes and meal plans to support you from day one.

You can pre-order your copy now and your support truly helps this work

find the people that it's meant for.

Thank you again for joining me, and I will see you next time!