Hashimoto’s and SIBO (Part 1 of 2)

Diet Matters with Hashimoto’s

For many people who struggle with Hashimoto’s, diet is a huge issue.

Yet, many doctors ignore the role of diet in the initiation, and progression of this and other autoimmune diseases.

But, if you have Hashimoto’s, and you are like a lot of people we’ve worked with, then you know that what you eat has a huge impact on your health and how you feel.

This just makes sense. Where is your immune system in your body?

Over 70% is found in and around your digestive tract. This is where it lives.

What you eat has a profound impact on autoimmune diseases like Hashimoto’s.

In this series of posts, we’ll examine a key factor in healing your Hashimoto’s by looking into something that is really common but often overlooked.

SIBO or small intestine bacterial overgrowth.

I recently attended a lecture taught by my teacher and mentor, Dr. Datis Kharrazian.

Dr. Kharrazian is a relentless researcher.

He is always exploring other people’s research and doing his own in order to help us understand why people are getting sick and how we can fix it.

In a recent lecture that I attended called “The Neuroendocrine Immunology of Small Intestine Bacterial Overgrowth”, he shared a lot of really valuable information on many aspects of SIBO that new research has revealed.

Why SIBO Matters to Someone with Hashimoto’s

Determining whether not you have SIBO can be really, really important for people with Hashimoto’s because of the role that the small intestines play in thyroid hormone conversion and absorption.

When you have Hashimoto’s and hypothyroidism this leads to problems with motor functions in the small intestine.

There are thyroid hormone receptors all over the gut. The vagus nerve fires into the gut.

If they aren’t getting enough thyroid hormone, things don’t move as well through there and that leads to overgrowth of bacteria.

And too much of this bacteria can interfere with levothyroxine absorption.

This is why some people take Synthroid, Armour, Cytomel, Naturethroid or another thyroid replacement hormone and it doesn’t feel like it’s working.

That’s because it isn’t.

With SIBO you can’t absorb thyroid hormone very well.

And autoimmunity shuts down T3 receptors.

Again, thyroid hormone doesn’t work if it can’t bind to receptors and can’t be absorbed.

So, even though you are taking thyroid hormone, it isn’t working – you have all the symptoms like fatigue, brain fog and memory issues, weight gain, hair loss, depression, etc.

The Small Intestine is Ground Zero for Autoimmunity

Many researchers also believe that autoimmune disease originates in the intestines.

A leaky gut or damaged intestine has been found in every autoimmune disease that has been tested including rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel disease (Crohn’s disease and ulcerative colitis), celiac disease, multiple sclerosis, type I diabetes and, yes, Hashimoto’s.

In the small intestine this damage leads to immune system stimulation, the wrong types of things in the blood stream and, ultimately, a systemic problem that results in the loss of self-tolerance.

This means that the immune system gets so overwhelmed it can’t tell what is our tissue and what is a bad guy that must be attacked.

Which Came First Leaky Gut or SIBO?

There are many causes of the breakdown of the intestines.

These include NSAID use, alcohol, gluten and other dietary proteins, bacterial overgrowth, environmental toxins and more.

And once this breaks down it alters the whole ecosystem of the gut.

It’s hard to know which came first.

And at the end of the day, it doesn’t really matter.

What matters is what causes it and what we can do to heal it.

Symptoms of SIBO

SIBO has a number of possible symptoms, but mostly these involve bloating, gas, diarrhea and/or constipation.

The hallmark symptom is bloating and discomfort after eating certain foods.

Basically here’s what happens.

The wrong type of bacteria end up getting into the small intestine. The migrate from the large intestine and take over.

They feed on certain types of foods like sugars, galactans, fructans and starch.

In reality, SIBO should be considered with abdominal discomfort after eating any of the following things:

– Starches
– Sugars/fructose
– Fructans
– Prebiotics
– Probiotics
– Fiber supplements
– Rice or pea powder from metabolic powders
– Galactans

You may notice that many of the foods listed here can also aggravate candida. And sometimes candida is blamed for what is actually SIBO.

5 Main Causes of SIBO

The causes of SIBO matter because when we understand the causes, we can figure out how to fix them.

These include:

1. Too little stomach acid.

Hashimoto’s and hypothyroidism leads to lower production of gastrin and stomach acid. This is super common.

And ironically, many people develop GERD or acid reflux and are prescribed proton pump inhibitors and antacids that just make everything worse.

(We’ve discussed this in depth in this post)

2. An immune suppressed gut.

Many factors can lead to immune suppression in the gut. 2 important ones are long term corticosteroid treatment and chronic stress.

In either case, lots of cortisol or corticosteroids cause the immune system to shut down and allows the party to get out of control.

With Hashimoto’s the body is under a great deal of physiological stress, all the time. So extra emotional stress and abnormally stressful events often result in people getting a lot sicker.

This is one of the reasons why.

3. Injury to the gut nervous system (known as the ENS or enteric nervous system)

The gut has been called the body’s “second brain” because it has it’s own nervous system and produces many of the neurotransmitters that are also produced in the brain.

Well, just like our other brain this can degenerate and break down with age and with diseases like chronic celiac disease, sceleroderma and IBS.

And just like neurodegeneration in the brain, this can be permanent. But also, just like the brain this second brain has remarkable plasticity and it can relearn things and rewire itself, too.

The gut brain and our main brain are both loaded with thyroid hormone receptors. With Hashimoto’s and hypothyroidism, there is often too little thyroid hormone or it’s not getting absorbed properly.

This can result in damage to the enteric nervous system (the gut brain).

4. Problems with the Vagus nerve

The Vagus nerve is a central highway for communication between the brain and the gut. When the vagus nerve stops firing into the gut this slows down everything.

This is a major cause of slower motility and constipation.

Thyroid hormone has a direct affect on movement through the entire gastrointestinal tract.

Thyroid hormones increase intestinal neurotransmitters, increase blood flow to the intestines and support the repair and regeneration of the intestines.

Hypothyroidism can slow movement through the esophagus, can affect muscle function in this area and can affect the nerves that cause movement.

Hypothyroidism also has an affect on the vagus nerve and this can lead both directly and indirectly to slowing movement through the intestines.

5. Anatomical or structural changes to the small intestines or illeosecal valve

Surgery to the gut (like appendectomy or resection), diverticulitis and scarring due to inflammatory bowel disease can all lead to this.

Hypothyroidism can lead to the loss of control of the ileosecal valve that is the doorway between the large and small intestine.

When this stops working as it should it lets lots of critters from the large intestine into the small intestine.

SIBO Has Degrees of Severity

Just like Hashimoto’s, SIBO has different degrees of severity. These are important because the more serious it is the more work you may have to do to resolve it.

I. Asymptomatic:

Abnormal small intestine bacterial overgrowth tests and mild or no symptoms.

Bloating after meals.

II. Moderate Symptoms:

Bloating with malnutrition and constipation.

Bloating with nutritional deficiencies.

III. Severe Symptoms:

Bloating with anemia, low albumin, low cholesterol

Bloating with weight loss, chronic diarrhea and malabsorption

If you are a person who has trouble taking supplements because you just react to everything, then you may fall into the more severe symptoms category.

Who Has SIBO?

Here’s an overview from the Journal of Clinical Gastroenterology on the prevalence of SIBO in other conditions:

15% of the elderly

33% of people with chronic diarrhea

34% of people with chronic pancreatitis

53% of people using antacid medication

66% of patients with celiac disease with persistent symptoms.

78% of people with IBS

90% of alcoholics

What really stands out for me there are 2 of those statistics.

More than half the people on antacid medication and 9 out of 10 alcoholics suffer from SIBO.

That shows you how destructive alcohol can be to the small intestines.

And, the fact is that alcohol degenerates the enteric nervous system of the gut very aggressively.

How Do You Test for SIBO?

In the conventional medical model there are 2 types of testing for SIBO.

Both are flawed and not definitive.

1. Direct: Endoscopic Aspiration and Culture

This is a direct endoscopic aspiration and culture of the small intestine.

This requires a gastroenterologist, it’s expensive, it’s invasive (they have to go in and get a sample).

The problem with this is that many of the bacteria removed from the small intestine can’t be analyzed because they don’t survive in culture.

Samples must be handled properly for accurate results.

To recap: It’s expensive, it’s invasive and sometimes tests don’t reveal all the bacteria involved.

2. Indirect: Breath Testing for Hydrogen and Methane

This type of testing involves breath testing for hydrogen and methane.

This test can be inaccurate if someone has recently had antibiotics.

It may not be useful in determining all species of bacteria.

The optimal window for timing for collection is different for different people because transit time is different for different people.

To recap: You may get false negatives due to different transit times or antibiotic use.

Actually, the best test for SIBO is a trial diet and/or a stool test that looks for invasive species.

In our next post, we’ll look at this diet and how to treat all 5 different causes of SIBO and the various levels of seriousness.



http://www.ncbi.nlm.nih.gov/pubmed/17698907 – SIBO and hypothyroidism -antibiotic therapy didn’t affect thyroid hormone levels

Link between SIBO and hypothyroidism


“It is markedly decreased in conditions in which there is a decrease in the effective small intestinal absorptive surface, including short bowel syndromes sprue, and other malabsorptive conditions.”

http://www.europeanreview.org/wp/wp-content/uploads/451-4561.pdf – Levothyroxine absorption in health and disease

http://gutcritters.com/thyroid-function-and-gastrointestinal-distress/ – LPS and thyroid receptors

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3099351/ SIBO Study

http://www.ncbi.nlm.nih.gov/pubmed/12388159?dopt=Abstract – Infection leads to poor thyroid hormone absorption

http://www.ncbi.nlm.nih.gov/pubmed/18372241 – LPS reduced T3

http://chriskresser.com/inflammation-strikes-again – Low T3 Syndrome



http://neurosciencestuff.tumblr.com/post/38271759345/gut-instincts-the-secrets-of-your-second-brain Great article on the enteric nervous system

http://www.ncbi.nlm.nih.gov/pubmed/16336493 : glial cels in the gut cause neurodegeneration

http://www.jneuroinflammation.com/content/7/1/37 : neurodegeneration in IBD

http://ajpgi.physiology.org/content/ajpgi/303/8/G887.full.pdf : enteric glia cells are protective, damage to them leads to neurodegeneration

Prevalence of small intestine bacterial overgrowth diagnosed by quantitative culture of intestinal aspirate in celiac disease. J Clin Gastroenterol, 2009 Feb; 43 (2): 157-161

The Neuroendocrine Immunology of Small Intestine Bacterial Overgrowth, lecture notes, Dr. Datis Kharrazian, November 2014.

The Paleo Approach, Sarah Ballantyne, PhD, Victory Belt Publishing 2013

About the Author Marc Ryan

So now, not only is it my profession, it’s my passion, and it’s personal. I’ve been joking with people lately saying it’s a blessing and a curse. A blessing because I really get it, and a curse because I really got it! ?

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