Chronic fatigue syndrome (CFS) is a complex, chronic medical illness that has a big impact on the lives of those dealing with it. It affects various parts of the body, including the nervous, immune, neuroendocrine and digestive systems. There is evidence to suggest that, in CFS, there is a dysregulation between these various bodily systems, which helps to explain the complex picture of symptoms that are seen in the illness.
Chronic fatigue syndrome has gone by various names over its time, including Myalgic Encephalomyelitis (M.E) and post-viral fatigue syndrome. In the 1980s, it was informally referred to as “Yuppie flu”, due to its widespread presence amongst 20–30-year-old working professionals. More recently, the term “Long COVID” has emerged onto the scene in the wake of the 2020 global pandemic. This is when the medical community observed a surge in patients reporting chronic symptoms following a SARS-CoV-2 infection which are much akin to CFS. While experts are still investigating whether Long COVID is a distinct condition from CFS, it’s certainly evident that there is a significant symptom overlap.
It is currently not known precisely what causes CFS. However, emerging evidence is beginning to provide some interesting insights about the factors that are at play in this condition.
CFS has a three-pronged structure, which can be broken down into three Ps:
Predisposition
It is widely recognised that there may be a genetic component associated with CFS. In 2001, a twin study examined concordance rates, which assess the likelihood that two individuals with shared genes will develop the same condition. The study’s findings indicated a significantly higher concordance rate among identical twins in comparison to non-identical twins, indicating that genetic factors may increase the risk of somebody developing CFS.
In 2020, a research grant was provided to further explore potential genetic connections to CFS. The Decode ME study, a collaborative initiative involving researchers, individuals living with CFS, caregivers, and advocates, is led by the ME/CFS Biomedical Partnership. This study is currently working to investigate genetic traits that might predispose someone to developing CFS. As our comprehension of CFS continues to advance, these efforts offer the potential to unveil more insights into the genetic foundations of the condition.
Precipitating Triggers
There is also substantial evidence suggesting that CFS often has a specific triggering event that initiates the onset of the illness. An examination of these precipitating trigger factors has revealed the following:
In my clinical experience, approximately 90% of the CFS patients I come across report recent infections as a trigger (primarily viral, although occasionally these can be bacterial or parasitic). This underscores why the term “post-viral fatigue syndrome” is often associated with many cases of the condition.
Nevertheless, it’s important to note that the onset of CFS is not exclusively tied to infections. I’ve also encountered clients who became ill following recent surgical procedures. In addition, some individuals have had glandular fever in childhood only to develop CFS years later after experiencing significant traumatic or stressful events. Others were asymptomatic carriers of infections before developing CFS. There have even been reports of CFS occurring after vaccination, breast implant surgery, and exposure to chemical toxins.
All of these scenarios serve as classic examples of a “haven’t been well since…” situation which is commonplace to trigger CFS.
Perpetuating Factors:
In addition to the elements that can predispose individuals to developing CFS and the triggers for its onset, there are additional factors that may continue to drive symptoms.
These sustaining factors encompass:
Examples of deficiencies: Nutrient shortages (e.g., B vitamins, iron, antioxidants such as CoQ10), insufficient thyroid function, as well as mitochondrial and adrenal insufficiency.
Examples of toxicities: chronic infections, allergies, oxidative stress, inflammation, imbalanced gut microbiota, emotional stress and trauma, in addition to environmental toxic burdens, such as increased exposure to heavy metals and mould.
Our digestive systems are crucially important to our overall health and longevity, so it comes as no surprise that research is linking the health of our gut with illnesses such as CFS.
One study reported that 92% of CFS patients experience irritable bowel syndrome (IBS), and, in most cases, IBS symptoms precede the onset of CFS itself.
Since many people with CFS also tend to experience digestive concerns, it raises the question: is there a gut origin for CFS?
Whilst it may be too early to say for sure, we do have some insights to turn to showcasing a gut-connection to chronic fatigue syndrome. For example, many studies have found dysbiosis in the microbiomes of CFS patients. This includes a reduced diversity of bacteria in the gut, with lower numbers of Bifidobacteria.
Bifidobacteria have been shown to keep the immune system in check and maintain the health of the gut barrier, which is why this might be a potential factor contributing to immune disturbances seen in CFS patients.
Infections within the gut may also be part of the picture in CFS. For example, parasitic infections including Giardia, Blastocystis hominis and Dientamoeba fragilis have been associated with triggering the illness.
Plus, if you were fascinated to learn that we are more bacteria than human, you may also be surprised to learn that we are, in fact, more virus than we are bacteria! Our bodies are host to various different viruses, which are collectively known as the virome. Just like bacteria, some of these viruses can cause disease, whereas others are completely harmless or even possibly beneficial.
Fun fact: it is estimated that up to 380 trillion viruses are harboured in the human body.
The gut contains the most abundant population of viruses compared with other areas of the body, with the majority being referred to as bacteriophages; these can live in and on bacteria, changing their genetic material and killing them.
It is increasingly evident that imbalances in gut microbiota, known as dysbiosis, are a common occurrence in CFS, often linked to a diminished variety of bacterial species in the gut. Given that viruses can influence the composition of gut bacteria, researchers are now asking the question, is dysbiosis in CFS somehow connected to changes in the gut virome?
Hopefully we will know more as research advances, but it is interesting to see the gut-connection to CFS expanding. There have also been studies associating a poorly functioning vagus nerve with some of the cognitive symptoms (such as brain fog) seen in CFS. Plus, the health of our gut is also correlated to the health of our thyroid, mitochondria, nervous system and immune system, which are areas of the body also implicated in the complex web of systems under stress seen in this illness.
Since there is such a long list of symptoms observed in CFS, many of which can resemble those of various other medical conditions, healthcare professionals must initially rule out alternative medical possibilities before making a diagnosis of CFS. As a result, CFS is considered a diagnosis of exclusion because:
Critics have referred to CFS as a ‘dustbin diagnosis,’ suggesting that it labels the symptoms without providing definitive explanations. However, the National Institute for Health and Care Excellence (NICE), which serves as a guiding authority for healthcare professionals in the UK’s NHS, has established a protocol. According to the NICE guidance, once a GP has made standard investigations and performed medical testing to rule out other illnesses, a CFS diagnosis is confirmed when the following symptoms have endured for a minimum of three months:
Note: while the above are the main symptoms that fulfil the primary criteria for a CFS diagnosis in the UK, diagnostic criteria for CFS can vary across the world*
Alongside consulting with your healthcare professional, here are some excellent charities which stand to support those affected by CFS in the UK. These include:
When it comes to supporting yourself from a nutrition, gut health and lifestyle standpoint, there are some excellent Nutritional Therapists (NT’s) out there who can offer help. Note: do seek out NT’s who are knowledgeable about CFS who can assist you best via the BANT practitioner directory, here.
Lauren Windas is a registered Nutritionist (mBANT, CNHC), Naturopath, Author, and co-founder of ARDERE. Lauren is also qualified as a Master Practitioner in Eating Disorders and Obesity (NCfED) and is trained in NLP. Lauren’s clientele often comprises of busy city workers and she holds a passion working with those who suffer with Chronic Fatigue Syndrome (CFS) and post-viral disorders, IBS, hormonal conditions as well as those struggling with their weight or relationships with food. Lauren’s journey into the world of wellbeing was sparked from her own personal health battles with CFS and poor gut health, which led her to release her debut book ‘Chronic Fatigue Syndrome: Your Route to Recovery’. She is passionate about educating people on how diet, lifestyle and functional medicine can be transformative for people’s health and happiness.
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