Page 39 - JCBP-3-3

Journal of Clinical and
Basic Psychosomatics Microbiota in psychosomatic disorders

individuals who consumed a probiotic mixture containing growth of species involved in fat metabolism. A study by
L. helveticus and B. longum for 30 days experienced Olson et al. demonstrated that a ketogenic diet in mice
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significant reductions in anxiety symptoms compared to increased the abundance of A. muciniphila, a gut bacterium
a placebo group. This study, along with others, indicates linked to improved gut barrier function and reduced
that probiotics may alleviate anxiety by reducing stress- neuroinflammation. Clinical evidence suggests that the
induced gut dysbiosis and modulating the gut–brain axis ketogenic diet may benefit individuals with anxiety and
through the vagus nerve, neurotransmitter production, neurodegenerative disorders by reducing oxidative stress,
and inflammatory signaling. neuroinflammation, and excitotoxicity. However, long-
Prebiotics, particularly those rich in pre-biotic term effects on gut microbiota and mental health require
fibers, such as inulin and resistant starches, promote the further investigation.
production of SCFAs, such as butyrate, which have anti- Psychological therapies, such as mindfulness, stress
inflammatory and neuroprotective effects. These SCFAs reduction techniques, and cognitive behavioral therapy
help modulate the gut–brain axis by enhancing the (CBT), have also been shown to improve gut health and
integrity of the BBB, reducing neuroinflammation, and mental well-being by modulating the gut–brain axis.
promoting the production of key neurotransmitters, such as Chronic stress is a well-known disruptor of gut microbial
serotonin and GABA. Freijy et al. conducted an 8-week, balance, leading to dysbiosis, increased gut permeability,
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2 × 2 factorial randomized controlled trial involving 119 and systemic inflammation. Mindfulness-based stress
individuals experiencing moderate psychological distress reduction has been shown to counteract these effects
and low pre-biotic food consumption. They found that by reducing cortisol levels and modulating autonomic
increased dietary fiber intake was associated with reduced nervous system activity. A study by Sun et al. found that
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symptoms of depression and anxiety, likely due to enhanced individuals practicing mindfulness exhibited improved
SCFA production and improved gut microbiota diversity. gut microbial diversity and a reduction in stress-related
Non-digestible fibers have also shown promise in managing symptoms, such as anxiety and GI discomfort.
mental health by selectively promoting the growth of
advantageous microorganisms, such as Bifidobacterium CBT, a well-established treatment for anxiety and
and Faecalibacterium. One study by Schmidt et al. found depression, has been shown to improve gut health in patients
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that supplementation with the pre-biotic GOS reduced with functional GI disorders, such as IBS. CBT addresses the
cortisol levels and anxiety in healthy volunteers, indicating cognitive and emotional aspects of stress and anxiety that can
that pre-biotics can reduce stress responses by supporting exacerbate gut symptoms while also improving gut function
beneficial bacteria that regulate the production of SCFAs by reducing the physiological impact of stress on the gut–
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and neurotransmitters. brain axis. A clinical trial by Lackner et al. found that CBT
significantly reduced both GI symptoms and psychological
Dietary interventions are another effective strategy distress in IBS patients, likely through the modulation of gut
for improving gut microbial diversity and mental health motility, immune function, and microbial composition.
outcomes. The Mediterranean diet, which is rich in
fruits, vegetables, whole grains, olive oil, and omega-3 Fecal matter transplant (FMT) is an emerging
fatty acids from fish, has been extensively studied for its therapeutic approach that involves transferring fecal
positive effects on both mental and gut health. This diet material from a healthy donor to a recipient to restore gut
has been shown to increase the abundance of beneficial microbial diversity. Originally developed for the treatment
gut bacteria such as Bifidobacterium and Lactobacillus, of recurrent Clostridium difficile infections, FMT has gained
which are associated with improved mood and cognitive interest as a potential therapy for both GI conditions and
function. In the Supporting the Modification of Lifestyle in mental health disorders. Studies have shown that FMT can
Lowered Emotional States trial, Jacka et al. demonstrated significantly alter gut microbiota composition, improving
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that adherence to a Mediterranean-style diet significantly gut barrier integrity and reducing inflammation. In mental
reduced symptoms of depression in individuals with health, early studies suggest that FMT may have therapeutic
moderate to severe depressive symptoms, with gut potential for conditions such as depression, anxiety, and
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microbiota changes linked to the production of anti- ASD. In the study by Kang et al., FMT led to significant
inflammatory metabolites and improved neuroplasticity. improvements in both GI and behavioral symptoms in
The ketogenic diet, which is low in carbohydrates and children with ASD. These findings are supported by pre-
high in fats, has also been investigated for its effects on clinical studies showing that transferring microbiota from
brain function and mental health. This diet alters gut depressed or anxious individuals into microorganism-free
microbiota composition by reducing the abundance of mice induced depressive- and anxiety-like behaviors in the
carbohydrate-fermenting bacteria and promoting the animals, demonstrating a clear link between microbiota

Volume 3 Issue 3 (2025) 33 doi: 10.36922/JCBP025040008