I have been looking for the link between bacterial and parasite gut infections and damage to the liver for some time now. Along with the positive stool results showing that I had the parasites Blastocystis hominis and Dientamoeba fragilis and the bacterial infection Klebsiella I also ordered a liver function test (LFT) where the blood is analysed for certain liver enzymes that indicate damage.
My liver function test came back slightly elevated. This concerned me more than my doctor at the time so I went about my business. A year later the same LFT test revealed still elevated liver enzymes and again the doctor (a different one this time) wasn’t concerned.
Looking into the test I was surprised to find that elevated liver enzymes on the test, particularly aspartate aminotransferase (AST) and alanine aminotransferase (ALT) become elevated when the liver cells are damaged. They actually rupture and release the enzymes into the blood that can be tested with the liver function test (1).
Learning this was enough to kick me into gear and very capable herbalist put me on milk thistle and a custom blend of herbs. Six weeks after starting the herbs I retested and this time the liver enzymes that had been elevated for over two years had come into the normal lab values.
Pretty impressive stuff.
Now putting on the functional medicine cap for a second let’s look beyond the symptoms (elevated liver enzymes and liver damage) and look to some possible root causes. What was causing my liver to suffer damage? That is the question.
The Gut-Liver Connection
It is pretty easy to understand that most body systems and the organs within them are interconnected. One body system impacts another. The nervous system interacts with the muscles in the body, the endocrine system produces hormones that impact everything from calcium homeostasis to digestion. Sometimes the interconnected nature of the body systems can seem so overwhelming that it can be difficult to know where to start.
As the table below shows the root cause of elevated liver enzymes can be many different things.
The connection between the liver and the gut is well summarised in a recently published review that we will be unpacking today.
The authors state that:
‘The liver is intimately linked to the gut via the portal vein, and exposure to gut microbiota and their metabolites translocating across the gut lumen may impact upon both the healthy and diseased liver. Modulation of gut microbiota could prove to be a potential therapeutic target.’
The review describes the portal vein that carries blood from the gut to the liver. When the gut flora are imbalanced or dysbiotic certain less-than-friendly bugs and their byproducts can pass through the intestinal barrier (leaky gut may be present in this circumstance) and make their way, via the portal vein, to the liver.
Surprisingly liver disease impacts a huge amount of people and it’s on the rise. Three hundred and twenty-eight outpatients were tested via biopsy of the liver. From those 328 patients 46% had non-alcoholic fatty liver disease (NAFLD). Diabetics had an even higher incidence of NAFLD at a rate of 74% in the 54 patients tested (4).
Pretty astounding numbers.
Back to the review.
The liver, as the first point of call from the gut, filters the gut flora’s by products and ingested food products. It takes the brunt in dealing with what we consume and what our microflora excrete, for better or for worse.
One study took 3 different groups of children and assessed their gut microbiota. One group had Nonalcoholic steatohepatitis (NASH) one group were obese but had normal livers and the third group was made up of healthy children. The table below shows the results.
The children with NASH and the children with obesity had a microbiome skewed towards the Bacteroidetes phylum which is made up of gram negative potentially opportunistic bacteria. While Bacteroidetes is generally one of the most numerous phylums in the human bowel many think that keeping it in check is beneficial for health. The NASH and the obese groups both had elevated Proteobacteria whose members include Campylobacter a pathogenic bacteria associated with gastroenteritis. They also had slightly lower levels of the Firmicutes phylum. Members of this group are fermenters and produce the short-chain-fatty-acids that fuel our intestinal cells. Firmicutes balances the Bacteroidetes phylum keeping it in check. On the other hand the healthy controls had elevated Bifidobacterium and Firmicutes, considered beneficial and lower levels of Bacteroidetes and Proteobacteria phylum considered less beneficial with some members being pathogenic.
The study suggested a link between liver derangement and a disrupted gut microbiome. They theorised that the connection could be in part due to the increase in microbes that produce alcohol endogenously, particularly Escherichia, and that alcohol metabolism produces reactive oxygen species leading to liver inflammation.
There is even a link between liver inflammation and liver cancer with up to 85% of the cases of hepatocellular carcinoma stemming from liver inflammation and cirrhosis (6).
Nourishing Your Microbiome
Now we get to the good part. What can we do with these findings.
If it is true that a disrupted gut biome can contribute to liver damage and derangement then focusing on manipulating the gut flora should be high on the list of interventions.
When it comes to manipulating the gut flora nothing seems to be more effective than diet. Prebiotics and colonic foods have been shown time and time again to have a massive impact on the ecosystem as a whole and should be incorporated if tolerated. There are certain situations where people don’t tolerate gut microbe feeding foods. It is best to work with someone who knows the terrain and can guide you through the process.
That said lactulose is a great candidate for increasing beneficial microbial fermenters like Bifidobacteria and Lactobacilli which helps to acidify the colon through the production of beneficial short chain fatty acids like butyrate.
Consumption of probiotic rich foods can help to tune the immune system and modulate the gut microbiome. Fermented foods like sauerkraut, kimchi and beet kvass can help as do probiotic supplements. There is even some focus on treating gut dysbiosis like SIBO with probiotics.
If you found this article helpful and have any experience to share then please leave a comment below.
References and Resources
- Review and Recommendations for the Component Tests in the Liver Function Test Profile
- Handbook of gastroenterology
- Review article: the gut microbiome as a therapeutic target in the pathogenesis and treatment of chronic liver disease
- Prevalence of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis among a largely middle-aged population utilizing ultrasound and liver biopsy: a prospective study.
- Characterization of Gut Microbiomes in Nonalcoholic Steatohepatitis (NASH) Patients: A Connection Between Endogenous Alcohol and NASH
- The role of the gut microbiome in the development and progression of liver cirrhosis and hepatocellular carcinoma