It is a debilitating condition that you may have heard of once or twice. And, contrary to popular conception, it goes beyond fatigue.
Chronic Fatigue Syndrome (also known as Myalgic Encephalomyetlitis) is a flu-like medical condition characterised not only by long-term fatigue but a whole host of other symptoms that limit a person's ability to carry out daily life.
Fatigue in itself is too common a symptom.
"The key defining feature is actually what's called post-exertional malaise. This involves a flu-like reaction following any form of exertion, trauma or activity that exacerbates stress," Chris Armstrong, researcher at the University of Melbourne's Department of Biochemistry and Molecular Biology, told The Huffington Post Australia.
With no simple cure nor treatment -- and a tendency to misdiagnose -- it has tested physicians and scientists alike for decades.
"The disorder itself is really complicated. It has been a long time since any consistent studies have found anything worthwhile for ME/CFS. So we've been narrowing in," Armstrong said.
What are the symptoms?
- Extreme exhaustion post-exertion
- Loss of memory of concentration
- A sore throat
- Unexplained muscle pain
- Headaches of a new type, pattern or severity
- Unrefreshing sleep
And so we turn to our evolving understanding of gut health -- dubbed the next big frontier in medicine -- to understand what causes and maintains this condition.
Armstrong is part of a team of researchers at Melbourne University who have been studying the metabolites (AKA products of metabolism) and gut microbiota in the faeces, blood and urine of those with ME/CFS.
Their research, replicated in later studies, has shown a microbial difference in those with the disorder. Essentially, the gut bacterial microbiome in chronic fatigue syndrome patients isn't normal.
Where's the link?
A recent study has uncovered new changes hinting that the composition of the gut could be skewing the body's metabolism -- or how our bodies convert food into energy -- of those with ME/CFS.
And the change is a subtle but telling shift in the body's source of energy production: from sugars to amino acids (the beads that make up protein).
"Our food gets broken down by bacteria and these things called short chain fatty acids ... Our study has shown an increase of bacteria that are better at fermenting amino acids to these acids," Armstrong said.
"No one has found any downsides to short chain fatty acids -- they are a positive thing that are being produced by the bacteria in our gut. But we do believe this increase in short chain fatty acids may be causative or additive to the metabolism alteration we see in those with the disorder."
We are trying to hone in on how this relationship exists for people with the disorder and we want to know whether we can improve symptoms by improving their gut health.
As a result, a cycle of increased short chain fatty acids and reduced amino acids leads to a lessened ability for the individual to create digestive enzymes and mucins which stabilise a healthy gut.
Such alterations may be behind or a part of associated fatigue symptoms.
"This cycle is our hypothesis as to possibly being important for maintaining the disorder, while not necessarily being the trigger," Armstrong said.
What does this all actually mean?
According to Armstrong, changes to the gut bacteria are common in a lot of disorders.
"This is a common trend -- we are trying to hone in on how this relationship exists for people with CFS and we want to know whether we can improve their symptoms by improving their gut health."
Now, Armstrong and his team are working on longitudinal studies that will make alterations to patient's diets to study the potential benefits.
"We might look at giving them more amino acids or more lipids in a metabolised form and seeing whether this aids them," Armstrong said.
"If we can induce improvement and notable changes in their bacteria and metabolism then we may develop markers and more importantly a system for monitoring and treating individual patients."
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