Chronic Fatigue in Your Gut Not Your Head

In April I reported a study demonstrating that probiotic supplementation had a beneficial effect on one of the psychological symptoms of Chronic Fatigue Syndrome (CFS). In that 2009 paper patients on the treatment for eight weeks were significantly less anxious than those taking the placebo product. Published in June this year a new study builds on that observation. The researchers at Cornell University first noted the frequent comorbidity of gastro-intestinal disorders with CFS, as well as evidence of abnormal immune response in individuals with CFS as indicated by markers of inflammation in the blood. They hypothesised that, taken together, gut microbiome diversity and levels of inflammation could predict who had a diagnosis of CFS.

This study compared the samples of 39 healthy people and 49 individuals with CFS. By looking at differences in the samples the researchers were able to identify disease cases with 83% accuracy. They found that those with CFS were significantly more likely to show signs of microbial translocation, where bacteria that reside in the gut break through the gut wall and enter the blood stream. Since they should not be present in this part of the body the immune system recognises these roving bacteria as intruders and launches an immune (inflammatory) response. This inflammation is associated with many of the symptoms of illness in CFS and other infections.

Compared to the samples of healthy individuals ME patients had reduced numbers and diversity of a type of bacteria called Firmicutes¸ typically the most abundant phyla in the human gut microbiome, as well as significantly lower amounts of types associated with an anti-inflammatory affect.

In the long-running debate about what causes Chronic Fatigue Syndrome the arguments tend to fall dichotomously: it’s either psychological OR biological in nature. Some research has shown a positive effect of psychotherapy in alleviating symptoms whilst others have found improvement with microbiome modification. The likelihood is, therefore, that a combined treatment approach will yield the best results for patients, helping them to manage both the physical and psychological symptoms of this debilitating disease. 

Giloteaux, L., Goodrich, J. K., Walters, W. A., Levine, S. M., Ley, R. E. & Hanson, M. R. (2016). Reduces diversity and altered composition of the gut microbiome in individuals with myalgic encephalomeylitis/chronic fatigue syndrome. Microbiome, 4:30.

Jason, L. A., Torres-Harding, S. Friedberg, F., Corradi, K., Njoku, M. G., Donalek., J., Reynolds, N., Brown, M., Weitner, B. B., Rademaker, A. & Papernik, M. (2007). Non-pharmalogical interventions for CFS: A randomized trial. Journal of Clinical Psychology in Medical Settings, 14, 275-296.

Borody, T. J., Nowak, A & Finlayson, S. (2012). The GI mircobiome and its role in Chronic Fatigue Syndrome: A summary of bacteriotherapy. Journal of the Australasian College of Nutritional and Environmental Medicine, 31, 3-8.

Probiotic Relieves Anxiety in Chronic Fatigue Syndrome (Pilot Study)

Chronic Fatigue Syndrome (CFS) or Myalgic Encephalopathy (ME) is a complex illness of unknown cause that has both physical and psychological symptoms. The major physical symptom is intense bodily fatigue, which is made worse by bouts of physical or mental exertion and is not relieved by sleep. Muscle and joint pain and bowel conditions such IBS are often also seen. Psychologically, people with a diagnosis of CFS often report feeling depressed and/or anxious and find it hard to concentrate. Although it is not clear what causes CFS there is a strong link to increased markers of inflammation (the body’s immune response to illness or infection) and disturbances in the gut microbiome. This observation is interesting because the gut is the crucible of the immune system and plays an important role in ‘teaching’ the immune system to respond appropriately to pathogens and in distinguishing the body’s own cells from invaders.

In a small but well-designed pilot study, participants with a diagnosis of CFS and comorbid depression and/or anxiety were randomly assigned to two experimental groups. The test group took three sachets a day of a probiotic (Lactobacillus casei Shirota) totalling 24 billion bacteria per day. The control group ingested three sachets of an identical looking placebo product. After eight weeks the patients were reassessed on the depression and anxiety scales.

At the end of the test period not only had there been an increase in the number of Lactobacillus in the patients’ guts but also increased numbers of Bifidobacteria, a different strain of bacteria that is associated with a healthy digestive system. This is noteworthy a) because it indicates that the introduction of one helpful strain can encourage the proliferation of another, b) because CFS patients tend to have low levels of Bifidobateria and c) because some strains of Bifidobacteria are known to improve blood levels of tryptophan, an essential amino acid that is the precursor of serotonin, a neurotransmitter linked to happiness and good mood.

The researchers also found that patients who had been taking the probiotic were significantly less anxious than at the start of the study, a valuable finding considering the significant burden of anxiety in this patient group. Importantly, the probiotic was well tolerated, which means that it did not cause any unwanted or unpleasant side-effects.

Rao, A. V., Bested, A. C., Bealune, T. M., Katzman, M. A., Iorio, C., Berardi, J. M. & Logan, A. C. (2009). A randomized, double-blind, placebo-controlled pilot study of a probiotic in emotional symptoms of chronic fatigue syndrome. Gut Pathogens, 1:6.