Leaky Gut | Does the permeable intestine lead to Hashimoto’s Thyroiditis?

Relating to the most diverse autoimmune disease, as for example the Hashimoto’s thyroiditis, the term “leaky gut syndrome” repeatedly emerges. But how does this syndrome manifest itself and in which context does it trigger autoimmune diseases?

If someone speaks about the Leaky-gut syndrome (LGS) then it means a defective or even leaking intestine mucous membrane. To be precise, there occurs a relaxation of the cell-cell connection (tight junctions).

Meanwhile, it has been found that this defective barrier in the small intestine plays a crucial role in whether autoimmune diseases even arise, or are triggered. Also this syndrome is partly responsible for how a chronic or even incurable disease, such as Hashimoto’s thyroiditis, progresses.

What does a Leaky-Gut syndrome do in the body?

As already mentioned, the leaky gut is a permeability of the intestinal mucosa. In a healthy body, this is the protective wall between the contents of the intestine and the bloodstream. Normally, the intestinal mucosa allows only water and important nutrients for the body to pass.

But in case of a damaged intestinal mucosa, food components, metabolites, pollutants, bacteria and toxins are repeatedly brought into the bloodstream. You could also compare that to a broken sieve. If it is intact, only the fine juice of berries is allowed to get through. But if there is a small crack in the dense mesh, the coarser pieces can pass also.

A healthy intestinal wall basically consists of four layers. Seen from the inside to the outside this would be the following:

How the Leaky-gut works

1. The intestinal flora (microbiota): This layer consists of our intestinal bacteria.

These have the task to protect our intestinal wall from pathogens, to produce enzymes and minerals, to remove mucus, and to train the immune system.

2. A mucous layer that binds pollutants and is transported out with the bowel movement.

3. A mucosal layer, which consists of separate skin cells that are connected to each other via the “tight junctions”.

4.The fourth layer is connective tissue.

Through a damaged intestinal mucous, poisonous and harmful substances, but also viruses, bacteria and fungi can enter our bloodstream, which are classified by our immune system as an enemy. Thus, it is only natural that it comes to an immune reaction. This means that the body emits inflammatory substances and at the same time antibodies are formed against these invaders. Basically, this would be a good thing.

But since these foreign substances, that have come  into the organism from the intestine,  are often very similar in their structure to the body’s own tissue structure, errors often occur. As a result, the immune system now also attacks the body’s own cells, which coincidentally have a similar molecular structure to those, that have entered the blood through the permeable intestine. In the end, the body starts falsely attacking itself and an autoimmune disease like Hashimoto’s thyroiditis develops.

Especially gluten in this context is a very big problem. Due to the molecular similarity between the thyroid tissue and the protein building block gliadin, a momentous confusion in the organism can occur.

If gluten enters the bloodstream due to the permeable intestinal wall, the immune system activates the release of antibodies that are supposed to attack and defend the incompatible gluten protein gliadin. But due to the structural similarity, also the tissue of the thyroid gland is falsely attacked and that quickly causes an inflammation of the thyroid gland.

But also against other foods, that are wrongly entering the bloodstream, corresponding antibodies are formed, so that simply may arise allergies and intolerances against them.

What symptoms speak for a Leaky-gut syndrome?

The permeability of the intestine usually has very different effects and comes with a variety of symptoms. Here is a small selection of the possible signs:

  • Food allergies / food intolerances
  • Autoimmune diseases
  • Small intestine bacterial overgrowth (SIBO)
  • Inflammatory bowel diseases
  • Digestive problems
  • Skin diseases, atopic dermatitis and eczema
  • General fatigue and drop in performance
  • Diabetes Type I
  • Rheumatism
  • Celiac disease
  • Fogged brain
  • Chronic headache
  • Mood swings
  • Depression and general mental symptoms
  • Nutritional deficiency
  • Allergies
  • Chronic abdominal discomfort like diarrhea, constipation, flatulence and abdominal cramps
  • Hair loss
  • Weight Loss

What are the causes of the Leaky-gut syndrome?

The Leaky-gut syndrome can be caused by:

If you look closer to the causes of the Leaky-Gut syndrome, it is obvious, especially with regard to the autoimmune disease Hashimoto’s thyroiditis, that these two factors are strongly influenced and closely related:

Wrong nutrition

A high intake of sugar and isolated carbohydrates via food, but at the same time too few supply of vegetables and fiber, the LGS often already is pre-programmed. In many cases also the wrong fats, like those from sausage and cheese, are consumed in larger quantities.

If  then perhaps a hypersensitivity to gluten or milk protein comes on top, good conditions already have been created for the development of a Leaky-gut – often without knowing  or noticing it immediately. But also undiscovered intolerances irritate the intestine permanently and thus ensure it for a permeability in the long run.


Many of today’s painkillers and antibiotics are a serious problem for the intestinal mucosa and the intestinal flora. Because antibiotic drugs attack the intestinal mucosa, and unfortunately destroy, beside the unwanted and harmful bacteria, also the health-promoting bacteria. Often after taking antibiotics, a fungal infection with Candida albicans is detected, which can spread unhindered by the intestinal flora that is disturbed by antibiotics.

A single antibiotic treatment causes damage in the intestine, which can be repaired by the body at the earliest after 6 months. With several, successive treatment with antibiotics, basically no complete regeneration of the intestinal flora can take place and a diseased gut is preprogrammed.

But also anti-inflammatory analgesics often damage the gastric and intestinal mucosa so much, that it can actually lead to internal bleeding. But even cortisone, radiation and chemotherapy seriously damage the healthy intestine.


Everyone knows that this stimulant is not really healthy in principle. But with regular alcohol consumption, the intestinal mucosa is damaged also, as with drugs or improper nutrition. But the mainly problem here is that, in a regular consumption of alcohol, the intestinal mucosa has no chance to regenerate naturally.

Intestinal fungi and parasites

Each of us houses the yeast fungus Candida albicans in the gut. But if he proliferates too much due to improper nutrition or even a higher dose of antibiotics, he may trigger the Leaky-gut syndrome. Because in higher concentrations it also damages the natural protective layer in the intestine. He multiplies so much that he strongly suppresses the healthy intestinal flora and then releases fungus toxins and fusel alcohols, which are toxic to our gut health and destroy the intestinal mucosa.

Heavy Metals

Nowadays we encounter heavy metals everywhere in our everyday life. But the main sources of heavy metals, such as mercury, lead, arsenic, nickel, cadmium and palladium, still are dental materials, air pollution, cigarette consumption and contaminated food. That dental materials are  the main source of heavy metals, is well known, but also the load in our foods is increasing.

According to the Leaky-gut syndrome, heavy metals do have a negative effect in many ways. Heavy metals irritate the intestinal mucosa, which already would be enough to cause a Leaky-gut. In addition, they destroy the entire intestinal flora, which again clears the way for fungi and parasites. Also heavy metals cause significant deficits in the mineral balance, what ultimately leads to a weak immune system, and again causes intestinal fungi and parasites.

Due to the lack of minerals, the body is no longer able to regenerate the intestinal mucosa and to rebuild it constantly. I can only emphasize again and again, that heavy metals are playing a central role, and not only in the case of a Leaky-gut syndrome. Also in relation to the Hashimoto’s thyroiditis, HPU / KPU and the adrenal fatigue, meanwhile a connection can not be denied any longer.


It has become well established that stress can make you sick. In combination with improper nutrition, medication and / or constant consumption of alcohol, even seriously sick. Now it is not the stress itself that threatens our intestinal health, but it triggers other factors, such as the infestation of Candida, which leads to a damage of the intestinal mucosa.

But stress also often leads to the so-called adrenal fatigue, in which the adrenals are no longer able to produce enough cortisol. Cortisol is anti-inflammatory and ensures appropriate wound healing. If too little cortisol is available because of stress, even apparently harmless foods can lead to inflammation in the intestine.

Lack of vital nutrients

Our entire organism depends on vital nutrients and vitamins in order to function smoothly. If there is a deficiency in this area over a longer period of time, the intestine becomes ill and the active functioning of our entire digestive system decreases sharply. Especially vitamin A and zinc are needed in sufficient quantity for a healthy intestine. While vitamin A is responsible for healthy mucous membranes, zinc is used to regenerate and heal.

Infections in the digestive system

You can quickly get bacterial, viral or fungal infections, which can lead to gastrointestinal complaints. If you do not live in a sterile glass house, you will not always be able to avoid it. Basically, for a healthy person such an infection is not a huge problem. But to restore this imbalance in the body, unfortunately nowadays drugs are administered very quickly, which again adversely affect the intestinal health. After all, antibiotics and other substances do not only attack the harmful bacteria, but also those which are responsible for optimal intestinal health.

Food intolerances

Many people who suffer from headaches, fatigue or concentration problems for a long time often do not know that they may be suffering from food intolerance. This can be allergies or also a gluten hypersensitivity. So it may be that food is being consumed over and over again, which is weakening the immune system and thus damaging the gut health. If such a food intolerance is disregarded or the causes are not combated, this can also trigger the Leaky-gut syndrome.

Metabolic disorders

In the metabolic disorders, especially the HPU / KPU sufferers have an increased risk of developing LGS. In hemopyrrollactamuria / kryptopyrroluria, enzyme defects lead to an increased amount of metabolic waste products in the blood, which are excreted via the urine with zinc, vitamin B6 and manganese.

The main cause of the increased risk for LGS is the lack of vital substances that the affected person does not have. This ultimately leads to the fact that the Leaky Gut syndrome is almost preprogrammed.

How is a Leaky-gut syndrome diagnosed?

Suddenly appearing food intolerances already can be an indication. Beside the classic lactose and fructose intolerance, these includes above all a Histamine intolerance. But too low secretory IgA in the stool often is an indication of the Leaky-gut syndrome.

In the past, the markers calprotectin, histamine and alpha-1-antitrypsin were frequently tested in cases of suspected Leaky-gut. But these have proved to be unreliable because they can also show abnormalities in other diseases. The two real and direct tests for the Leaky-gut syndrome today are the slightly outdated lactulose-mannitol test and the current zonulin test in the blood.

The disaccharide lactulose usually is not absorbed in the small intestine because the body cannot metabolize it. But in a Leaky-gut syndrome, the lactulose enters the blood in large quantities through the permeable intestine and is subsequently detected in the urine.

Mannitol, on the other hand, is a simple sugar that is always completely absorbed by the small intestine and that can later be measured in the urine. From the ratio between the measured mannitol and the lactulose, concrete conclusions about a Leaky gut can be drawn.

Zonulin is a protein that is able to open the tight junctions of the intestinal mucosa and thus favors the Leaky-gut. If increased zonulin levels in the blood serum are measurable, this is an indication of the Leaky-gut syndrome.

How to tackle the Leaky-gut syndrome

First and foremost, your own actions against the LGS result from the possible causes. This means that a change of nutrition will help your intestine to regenerate and become healthy.

With a change of your nutrition and an appropriate diet you can:

  • Better protect the mucus layer in the intestine
  • Rebuild the intestinal flora
  • Contribute to the regeneration of the intestinal mucosa
  • Inhibit inflammation

In detail this means, that you can achieve a lot by changing the nutrition. In the first place, you should make sure that as many of your foods as possible are rich in probiotic and prebiotic ingredients. For example, enrich your diet with homemade milk kefir, fermented vegetables or even yoghurt.

In addition, you should increasingly eat artichokes, asparagus, eggplant or even legumes, for example. Because these contain nutrients that help the natural and healthy bacteria in your gut to regenerate faster.

In addition, you should increase the intake of fiber. Because vegetables, seeds or even nuts do contain those substances that are known to help the intestine that the fungi can be excreted faster. But here it is important that you consider that you tolerate these foods well.

To help your gut with the natural regeneration, especially the intestinal mucosa, it is helpful to supplement your weekly meal plan with L-glutamine. Beef, spinach and also parsley, which are particularly rich in glutamine, can serve this purpose. To be on the safe side, L-glutamine also should  be supplemented in powder form. Usual dosages of the amino acid are 5-20g a day.

In addition, dietary supplements are a great way to provide your body with vitamins A, C and D3 daily, as well as NAC, zinc, butyrates, lecithin, rhodiola, and herbal enzymes. But also iron, selenium, calcium, magnesium, co-enzyme Q10 and high-dose probiotics should not be forgotten.

For a relieve of the entire system and a bowel rehabilitation, bowel irrigation and / or colon hydrotherapy are conceivable. In this way you help the organism to gently remove toxins and waste products, and to stimulate the intestinal peristalsis.

In general, the Leaky-gut Syndrome, with…

  • a specific diet,
  • the reduction of stress and the avoidance of stressful situations,
  • the replenishment of nutrients and vital substances

Can get in control very well.

Experience shows that already a specific diet and the supply of nutrients and vital substances attenuate or completely eliminate other causes of LGS. Thus again and again it is shown that with a balanced and healthy diet the adrenal glands react less stressed and recover better, simply because, among other things, the altered nutrition also makes your sleep better and deeper.


Leaky-gut syndrome is closely related to autoimmune diseases such as Hashimoto’s thyroiditis. It can trigger this disease and also strongly influence it.

The syndrome itself can be manifested by other conditions, or it may be due to wrong nutrition, massive consumption of alcohol or constant use of medication, just to name a few causes.

In principle, the Leaky-gut syndrome is significantly responsible for the fact that harmful and poisonous cells from the intestine pass through the bloodstream into the organism, because in this syndrome, the intestinal mucosa is damaged and permeable.

LGS is not always easy to diagnose, especially in its early stages. The causes of a leaky gut syndrome can be different. In order to get it under control, a healthy lifestyle and the change to a specific diet are recommended, so that the intestine can regenerate again.

In terms of the autoimmune disease on its own, Leaky-gut is not only a trigger, but also a constant companion, which can make the disease progress more quickly or co-determine the entire course of Hashimoto’s thyroiditis.

Image source:

  • leaky-gut-sketch: © Ghazi-Michael Ayed
  • leaky-gut: © Constantinos – Fotolia.com