The Impact of the Gallbladder on the Microbiome

The World Within You:  The Microbiome

• Scientists have long known that the human body coexists with trillions of individual germs, what they call the microbiome. 

• Microbes are organisms too small to be viewed with the naked eye. They can be single- or multi-celled and include bacteria, algae, archaea, protists, fungi, and viruses. Typically, we each play host to around 1000 different species of microbe, with as many as 7000 different strains, or subtypes, found in the gut alone. The specific composition of each human microbiome is unique, like a fingerprint. The main focus of microbiome research is its role in health and disease.

  That some microbes have a negative impact upon health is widely known. For example, fungi cause thrush, aspergillosis and athletes foot; bacteria cause salmonella, tuberculosis and syphilis; viruses cause the common cold, influenza and AIDs. Microbes are also thought to induce around 20% of all fatal cancers, and have been associated with multiple sclerosis, diabetes and coronary artery disease. Whether or not a species of microbe promotes or undermines good health often depends upon its interactions not only with its human host, but with neighboring microbe species and the wider environment.

  The microbial population of the gastrointestinal tract is extremely dense, made up mostly of bacteria. While a core community of gut microbes—approximately one third—is common to most healthy adults, the composition of each gut microbiota varies according to factors including genetics, diet, age, state of health and geographical location. Microbes are considered essential to digestion. The gut microbiota breaks down substances that the gut alone is unable to digest and is also involved in synthesis of vitamins.

• Our microbiomes help us digest food and fight disease, all the while evolving fast and flexibly in service of their own interests.

Gallstones are associated with an increase of certain bacterias, which suggests an overgrowth of bacteria previously linked to gastrointestinal disorders.  There are three common gut bacterial in patients with gallstones, indicating a correlation between these bacteria and gallbladder attacks

Bile and the microbiota
The biliary tract is the path by which bile is processed by the liver and gallbladder, then transported to the first part of the small intestine. In gallstone patients, high levels (around 70%) of gut bacteria were detected in the biliary tract.  Certain bacteria in the biliary tract of patients increase the risk of gallstone formation

Manipulating the microbiome could be an important part of the prevention and treatment of gallstones. Although more studies on the GI microbiome are needed, results indicate that prebiotics, dietary changes, fermented foods etc. could be useful in the prevention and treatment of gallstones.

Imbalances in gut bacteria have been implicated in the progression from liver disease to cancer. 

There are trillions of microorganisms in the human microbiome — they outnumber their host's cells by around ten to one — and their exact role in health and disease is only now starting to be explored. Studies have found that people with non-alcoholic fatty liver disease have a different composition of bacteria in their gut from healthy individuals, various factors — including a high-fat diet, alcoholism, genetic susceptibility and the microbiome — can each contribute to the progression from minor to severe liver damage, and from severe liver damage to cancer.

Whatever comes from the gut enters the liver and is processed through the gallbladder.  As blood leaves the intestines it passes through the liver, carrying nutrients extracted from our food. It also carries our own digestive chemicals as well as fragments of the bacteria that live in the digestive system (such as bits of DNA and cell walls) and their metabolic by-products. Some of these by-products help us to access energy and nutrients in food, but some are toxic. 

The liver has several crucial functions, and it does more than just filter toxins and produce digestive chemicals.  The gallbladder is not a useless organ but instead works as a means to process and filter in conjunction with the liver.

The liver and gallbladder have an important role in immune surveillance and helps to maintain bacterial balance in the gut. Specialized cells in the liver and intestines monitor the microbiome by keeping tabs on bacterial by-products as they pass through. These cells can detect infections and help to fight them.  They can also pick up on subtler changes in the bacterial populations in the gut. When certain types of bacteria become too numerous — a state called dysbiosis — the immune system becomes activated and triggers inflammation, although at a lower level than it would for an infection. 

Immune reactions aimed at fighting infectious bacteria and other foreign invaders can have off-target effects that lead to disease. Dysbiosis causes inflammation that contributes to the worsening of non-alcoholic fatty liver disease. 

The key to maintaining balance of the various species of bacteria in the gut is the health of your gallbladder, without a gallbladder the liver function is taxed and bile is insufficiently managed. An out-of-balance microbiome promotes a constant state of inflammation, which can contribute to all kinds of problems throughout the GI tract, As an inflammatory process: these same immune reactions that help the body to fight infection and disease can also promote unchecked cell growth.

Out of balance

The liver generates bile acids, which are stored in the gall bladder and are released into the intestines to digest fatty foods. They act as a kind of digestive detergent, helping the body to take up dietary fat along with fat-soluble vitamins. The acids then get absorbed by the intestines and passed back to the liver, which sends them back to the gall bladder.

Some gut bacteria chemically alter these bile acids to produce secondary bile acids, which are toxic to humans and even to certain bacteria. Fat is carried in the same way by these secondary bile acids and follows the same path from gut to liver to gall bladder but can't be processed as effectively without your gallbladder.

An abundance of these secondary bile acids has been connected to obesity. Some of the earliest research on the human microbiome, demonstrated that the balance of gut bacteria in obese people is different from that in people of healthy weight. In particular, obese people tend to have greater numbers of the bacteria that produce secondary bile acids. The result is a fundamental change in the composition of the microbiota in the intestine and can cause dysbiosis.

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Researchers are looking for ways to understand the composition of people's bile acids, they believe it might be possible to get microbiomes back in balance by treating them with 'good' bacteria that have been genetically engineered to produce an enzyme that converts secondary bile acids back to their primary form.

There is also some early clinical evidence that specially formulated probiotics — cocktails of good bacteria — can bump the microbiome back into balance and that delivering bacteria to the gut can have positive therapeutic effects on the liver.

At Living Proof Institute we believe a balanced microbiome is the difference between health and a premature loss of vigor and vitality.  You can choose to feel good again, contact us to arrange a consultation to learn more.