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.

Healthy Diet Linked to Reduced Risk of Depression

In 2015 a large Spanish study reported results showing that improvements in diet reduced a person's likelihood of developing depression. Similarly, a new correlation study of Iranian adults (average age 36 years) has demonstrated a statistically significant relationship between healthy diet and reduced rates of depression. The researchers assessed the diet and lifestyle of over 3000 people - looking at their eating habits, weight, BMI, smoking status and levels of psychological distress - and compared them against measures for anxiety and depression. They found that non-smokers were less likely to be anxious than smokers and those with healthier diets were 29% less inclined to be depressed than those with poor diets. Further research is required to understand the predictive features of these results.

Saneei, P., Esmaillzadeh, A., Keshteli, A. H., Reza Roohafza, H., Afshar, H., Feizi, A. & Adibi, P. (2016). Combined healthy lifestyle is inversely associated with psychological disorders in adults. PLoS One. DOI: 10.1371/journal.pone.0146888

Psychotherapy Reduces Physical Symptoms in Irritable Bowel Syndrome

Irritable Bowel Syndrome (IBS) is the name given to a collection of abdominal and digestive symptoms. Typically suffers present abdominal pain and bloating, diarrhoea or constipation. Doctors are unclear as to what causes the symptoms but have linked the syndrome to altered immune function, stress and inflammation and, in some instances, abnormalities in the gut microbiome. Additionally, there is no known cure for IBS leaving sufferers in ongoing pain and discomfort that significantly impairs their quality of life.

A meta-analysis published this year has shown that psychotherapy is an effective long term treatment for reducing symptom severity in IBS. The researchers included only high-quality (random controlled trial) studies and the final analysis included data from a pool of 2290 individuals. Trials included standard psychological therapy as well as relaxation technique training, individual and group treatments and therapy provided in-person or by a therapist online.

Psychological treatments were shown to be effective both at short term (1-6 months) and long-term follow (6 month-one year); the treatment worked and the effects lasted. This study follows an earlier(2) meta-analysis that showed psychotherapy to be as effective as antidepressant medication at improving quality of life for IBS sufferers, but that psychotherapy was more effective than medication at reducing subsequent healthcare costs.

1. Laird KT, Tanner-Smith EE, Russell AC, Hollon SD, Walker LS, Short- and Long- Term Efficacy of Psychological Therapies for Irritable Bowel Syndrome: A Systematic Review and Meta-analysis, Clinical Gastroenterology and Hepatology (2016), doi: 10.1016/j.cgh.2015.11.020.

2. Creed, F., Fernandes, L., Guthrie, E., Palmer, S., Ratcliffe, J., Read, N., Rigby, C., Thompson, D., Tomenson, B. on behalf of the North of England IBS Research Group. The cost-effectiveness of psychotherapy and paroxetine for severe irritable bowel syndrome.  Gastroenterology, 124, 303-317.

Omega-3 Fats Are Effective Treatment for Depression – Meta Analysis

The varied literature on the effects of omega-3 supplementation on depression can throw up conflicting results depending on the structure and size of the individual studies. Some researchers will look at the components of omega-3s together, some separately; some for two weeks and some for two months. In order to arrive at a coherent answer to the questions of the role of omega-3 fats on depression a group of Italian researchers conducted a meta-analysis. They pooled the studies conducted on patients with a diagnosis of major depressive disorder (MDD) and those who exhibited depressive symptoms but who did not have a clinical diagnosis. The average length of treatment with fish oils was 16 weeks. The analysis revealed a significantly positive effect of fish oils (particularly EPA) in alleviating symptoms in both patients with MDD and those without a diagnosis showing that these essential fats are an effective treatment for primary depression. 

Grosso, G., Pajak, A., Marventano, S., Castellano, S., Galvano, F., Bucolo, C., Drago, F. & Caraci, F. (2014). Role of omega-3 fatty acids in the treatment of depressive disorders: a comprehensive meta-analysis of randomized clinical trials. PLoS One, 9 (5), e96905. ECollection.

Serum Vitamin D Predicts Cognitive Performance in Adults

Much of the research on the relationship between vitamin D and cognitive function has been conducted on older people or individuals who have a diagnosis of Alzheimer’s Disease or other dementia. This is because older people are less able to synthesise vitamin D in their skin and because dementia is typically a disease of aging. A study published in August 2015 looked at the relationship between vitamin D status and cognitive function in two cohorts of healthy individuals; those aged 30-60 and 60+. Research on disease-free groups is important because it allows us to look at the potential effect that nutritional deficiency has on the general population and on sub-clinical (no diagnosis) functioning. That is to say that we can learn more about how dietary insufficiencies might be affecting the general population long before disease onset. This information allows us more opportunity to intervene with treatment.

In this study of vitamin D in the blood were strongly associated with the degree of cognitive impairment on tests of visual spatial memory (recalling and recreating a complex shape) and processing speed. In this study lower levels of vitamin D were associated with poorer performance on these tests even in people aged 30.  This study complements a growing body of research that is demonstrating a relationship between vitamin D status and brain function (including influence on mood and anxiety disorders).

There is also growing concern worldwide about the ‘pandemic’ of vitamin D deficiency and the many health concerns it is associated with such as osteoporosis, fractures, and increased risk of some cancers and autoimmune diseases. It is estimated that at least 50% of people are vitamin D deficient and the situation is worse for those of with dark skin as the melanin pigment blocks the action of vitamin D synthesis in the skin. Food sources of vitamin D include oily fish (salmon, sardines and mackerel), eggs and fortified cereals, though few people are eating sufficient amounts of these foods to keep their levels topped up, and vegetarians and vegans need to be very thoughtful about their food/supplement choices to ensure adequate levels.

Reference

Darwish, H., Zeinoun, P., Ghusn, H., Khoury, B., Tamim, H., and Khoury, S. J. (2015). Serum 25-hydroxy vitamin D predicts cognitive performance in adults. Neuropsychiatric Disease and Treatment, 11, 2217–2223.

Healthy Diets Reduce Risk of Depression

A large (15,000 participants) Spanish study has shown that diets high in nutrients are linked to a reduced risk of depression. This study has generated a lot of interest not only because of the large cohort size, which makes the results more generalisable, but because it is thought to be the first to follow healthy individuals and track, over 10 years, those who went on to develop illness and disease.

The researchers looked at three diets:

• Mediterranean Diet – characterised by the consumption of vegetables, legumes, fruits and nuts, cereals, fish and seafood; low intake of meat and dairy products, and moderate alcohol intake.

• Vegetarian Dietary Pattern – a kind of ‘flexitarian’ diet that promotes eating plant foods (including potatoes) most of the time but allowing for a little meat

• Healthy Eating Index- promotes eating larger amounts of vegetables, fruits, whole-grain bread, nuts, beans and pulses, omega 3s and unsaturated fats, and smaller amounts of sugar-sweetened beverages and fruit juice, red/processed meat, trans fats, and alcohol.

As part of the study the researchers also looked at activity levels, BMI, health history and vitamin supplementation, and the analysis was controlled for a number of variables including age, sex and smoking status.

For the statistical analysis the levels of adherence were split in to five groups (quintiles). So on a scale of 1-5, those in group 1 ate the least healthy diets while those in group 5 were paragons of healthy eating. The results showed that those in groups 2-5 had a 25-30% reduced risk of developing depression than those in group 1. Interestingly, there was a plateau in this effect once the respondents had moderately good diets. The researchers believed this to be due to a threshold effect; once you are consuming adequate amounts of a nutrient there is no additional benefit of consuming larger quantities of it.

The researches did not highlight any individual food or nutrient as being particularly important or protective. In fact they pointed out in their discussion the inconclusive results from other studies that looked at the relationship between individual nutrients (vitamins, minerals or fats) and depression. However, this and other studies have demonstrated the strong relationship between the quality of the overall diet and risk of depression. It is likely that it is the interaction of different compounds from various foods that offers most protection not just to depression but to overall health. 

Reference

Sánchez-Villegas, A., Henríquez-Sánchez, P., Ruiz-Canela, M., Lahortiga, F., Molero, P., Toledo, E., & Martínez-González, M. (2015). A longitudinal analysis of diet quality scores and the risk of incident depression in the SUN Project. BMC Medicine, 13, 197-197.

Probiotic Alleviates Stress and Anxiety

We have known for some years now that there is a comorbidity between psychological problems such as depression and anxiety and gastrointestinal disorders. That is to say people who present with these psychological problems often have a gut issue at the same time and vice versa. Recent research that has started to explain some of the processes underlying this relationship and the term given to this connection is the ‘gut-brain axis’. The community of bacteria in the gut is central to the gut-brain axis with the bacteria playing an essential role in nutrient absorption and production, inflammation and immunity amongst many others.

Much of the research into the gut-brain axis is of potential treatments: the researchers are looking to relieve a particular disorder and so the results can often only accurately be applied to groups who suffer from that disorder. However, a recently presented study looked at the effects of probiotic (beneficial bacteria) supplementation on healthy people.

Researchers from Ireland put 22 male participants through a battery of tests to assess their cognitive performance, perceived stress and stress hormone levels before and after a four-week course of a daily supplement of the bacteria Bifidobacteria longum. At the end of the study the participants reported feeling less anxious and stressed, had significantly improved cognition scores and were producing lower levels of stress hormones.