Gut-Liver Axis

The liver is literally downstream of anything in the gut.

Poor gut health, over time leads to poor liver health. And 39% of non alcoholic fatty liver disease (NAFLD) patients have leaky gut. Although metabolic syndrome is the strongest factor in NAFLD, gut dysbiosis is tightly linked to both metabolic syndrome and NAFLD.

Non alcoholic fatty liver disease (NAFLD) is an epidemic – it is a disease that has rapidly spread to a large number of individuals within a short period of time. It has a world wide prevalence of 25% and in the USA as much as 30% of the population has NAFLD, including close to 10% of children aged 2-19. Fatty liver disease is when there is excessive alcohol consumption, which clearly damages the liver. Non-alcoholic fatty liver disease is when there is not excessive alcohol intake.

In Beyond Digestion, I talk a lot about how gut health connects to the health of the rest of your body. The gut-liver axis is no exception.

What does the liver do for you?

Answer: lots! The liver is the largest gland in the body, the second largest organ (skin is the first). It is responsible for:

  • metabolism
  • immunity
  • digestion
  • detoxification
  • vitamin storage

What damages the liver?

  • high fructose diet (processed and packed foods, soda pop)
  • high saturated fat diet
  • excessive alcohol intake
  • overeating
  • poor gut health
  • viruses like hepatitis
  • vitamin A or D deficiency
  • lack of omega-3’s
  • gut dysbiosis
  • antiviral drugs
Alcohol, if consumed, should be responsibly.
That means not every day, and in a day, no more than a glass for women or two for men.

Excessive fructose intake increases the levels of the Firmicutes family of bacteria and an overgrowth of Clostridium species upregulate expression of genes that are related to fat metabolism, which may lead to the accumulation of hepatic triglycerides, increasing the risk for NAFLD.

The liver, via the hepatic portal vein, is constantly exposed to the metabolites from digestion and microbiota in the gastrointestinal tract. When there are lower levels of Bacteriodetes, other bacteria flourish and promote the condition of small intestinal bacterial overgrowth (SIBO). Regardless of the strain, an overgrowth of gram negaive bacteria results in elevated levels of inflammatory bacterial toxins, called lipopolysaccharides, and these are associated with a rise in inflammatory liver response.

An overgrowth of Candida albicans, a natural occurring fungus in the gut, which causes a lot of sugar cravings, can also damage the gut lining and subsequently the liver.

There is also something called auto-brewery syndrome (ABS), whereby an imbalanced gut microbiome can ferment its own alcohols after consumption of a carbohydrate-rich meal. ABS is linked to extreme overgrowth of yeast. Just like yeast ferments wine or beer, it can ferment things in your gut, too. Imagine getting a buzz off a bagel. With ABS, that’s entirely possible. Do you experience gas, pain, bloat, headache, joint pain, or feeling hungover without the party? These are all symptoms of ABS. Fungus and yeast are not always to blame. There are alcohol producing bacteria such as Klebsiella pneumonia. Interestingly enough, it is found in higher amounts in those with NAFLD.

Who is at risk for NAFLD?

Asides to those who are overweight, have high blood pressure, high fasting blood sugar, and high triglycerides and LDL cholesterol, those with PCOS, un-managed hypothyroid or celiac disease, vitamin A or D or zinc deficiency, and even those who have received antivirals may be at increased risk of NAFLD.

Signs of NAFLD:

  • Nothing
  • Feeling unwell, irritable
  • Abdominal pain 
  • Weight gain and swelling
  • Itchy skin all over
  • Dark urine loss of appetite or a tendency to bruise easily
  • May also notice yellow looking skin or whites of the eyes
  • Brain fog, memory slips, anger, irritability
  • Erratic sleep patterns
  • Awake 1-3am/tired in afternoon 1-3pm.

If you are experiencing any of the above, it may be time for a health appointment that focuses on the health of your liver. After every gut reset, it is important to follow with liver health support. I’d be happy to discuss your needs, order necessary lab work and suggest natural interventions to help you recognize patterns, remove obstacles and get back in the saddle of good health.


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