The human digestive tract is strongly connected to most, if not all, of our major organs.
Look no further than the fact that you’ll likely have heard terms such as the gut-brain axis and the gut-skin axis, but did you know there is a gut-liver axis too?
Indeed there is!
And it has generated significant scientific interest as a target for intervention in the management of NAFLD [non-alcoholic fatty liver disease], which is the subject matter of my latest book.
Essentially, the liver is closely connected to the digestive system both in proximity and through physiological systems (known as the portal system, which connects them) such that proposed imbalances in the GI tract (imbalances between good vs bad bacteria, etc) can ultimately damage the liver in part through the release of inflammatory compounds that occur in this sub optimal state.
It’s for this reason that the concept of enhancing gut balance through the use probiotics (healthy bacteria) and prebiotics ( special types of fibre, which acts as “food” for good bacteria) could potentially lead to positive effects on the liver.
When taken together, a combination pre+probiotic supplement is generally referred to as a synbiotic, the term I will be using going forward in today’s article and the subject matter of the content ahead.
Given that I’m right in the thick of the promotional period for my new book – The Essential Diet For Fatty Liver Disease – I’m taking every opportunity possible to explore some novel topics around liver nutrition.
So let’s get right to it, and OH if you like the type of fun I get up to it in today’s post, you’ll absolutely adore my new book so be sure to pre-order your copy today!
Synbiotics For Fatty Liver Disease
The 2020 ESPEN Clinical Nutrition Guidelines For Fatty Liver Disease have this to say about the use of probiotics & synbiotics in the management of NAFLD:
“Nutritional supplements containing selected probiotics or
synbiotics can be used to improve liver enzymes in NAFL/NASH patients.”
These conclusions were drawn based on the results of a number of promising randomized controlled trials looking at liver health outcomes following a synbiotic intervention.
One such trial, a 2014 study out of the American Journal Of Clinical Nutrition, looked at the results of a 28-week supplementation cycle with a synbiotic in people living with NAFLD.
The study found that, in addition to decreased liver enzyme levels, there were decreases noted in a number of biological inflammatory markers such as C-reactive protein and TNF.
The amount of scarring on the liver, known as fibrosis, was also less in the group who took the synbiotic vs the placebo.
In this particular study the synbiotic supplement contained a 7 strain blend of various types of Lactobacillus and Bifidobacteriuma type probiotics and used FOS (fructooligosaccharide) as the prebiotic fibre.
Natural food sources of FOS include onions, garlic, asparagus and bananas – foods which may be reasonably recommended to be considered for those living with NAFLD.
While I’m in no way endorsing or promoting this particular product, I did a quick search on Amazon to identify an synbiotic that shared these characteristics and this particular product appears to share some of the characteristics of what was noted in this study.
Another randomized controlled trial out of Digestive Diseases & Sciences found that , over a 24-week period, the FOS prebiotic combined with a single strain probiotic (Bifidobacterium longum) yielded similar positive results and may have contributed in some capacity to improving insulin resistance and reducing liver fat storage.
It does appear the current state of the scientific evidence supports a promising role for synbiotic supplementation over an extended period as complimentary management tool for improving relevant outcomes in NAFLD.
The extent to which these supplements do so and their relative importance to other lifestyle interventions surrounding diet and exercise, is perhaps less clear.
Until next time,
Andy De Santis RD MPH