While previous animal studies have suggested a significant impact of the gut microbiota on the development and maturation of brain networks that underlie emotional behaviour, fewer studies have been conducted on humans.
Intake of a galacto-oligosaccharides (GOS) prebiotic over 3 weeks has been shown to lower the secretion of the stress hormone cortisol and emotional processing in healthy adults, suggesting that GOS intake may be useful in modifying anxiety-related psychological mechanisms. However, reviews and meta-analyses on the efficacy of prebiotics for reducing anxiety symptomology are mixed, calling for further well controlled trials in human participants.
The current research team, including an employee of FrieslandCampina, conducted a four-week trial involving 64 women, aged 18–25, with self-reported anxiety. The women were blindly randomised to receive a daily dose of Biotis GOS (7.5 g powder containing around 5.5g GOS) or a placebo supplement for 28 days.
Participants completed baseline and end of study surveys to assess their general health, including their sleep quality, mood and stress levels. Participants were also provided with stool-sampling kits to self-collect faeces for gut microbiome sequencing analysis. Brain imaging was employed on a sub-sample of participants to measure key emotion regulation regions, allowing for further understanding of how changes in the gut microbiome may relate to brain functioning.
A total of 48 participants completed the study - 23 in the GOS group and 25 in the placebo group. The resulting data reveal that after 28 days, the group receiving Biotis GOS reported improved mental well-being and reduced anxiety levels, while the microbiome sequencing analysis showed they had better gut health, characterised by significantly increased Bifidobacteria levels, compared to the control group, adding to the evidence that Bifidobacterium bacteria may be a driver of improving mental well-being.
This was the first human trial to demonstrate a clear link between GOS consumption, gut microbiota composition and mental well-being, according to its authors.
These findings “open the door for prolific, clinically-proven innovation in the supplement and functional food sectors,” according to André Groeneveld, Discovery Manager at FrieslandCampina Ingredients.
The authors suggest further research is required with improved power considering the small-medium effects identified here.
Commenting on the study, Vicky Davies, Global Marketing Director at FrieslandCampina Ingredients, said, “Research into the gut-brain axis is still a relatively new field, so it’s very exciting that this study has provided further evidence of the link between the gut microbiome and mental well-being, as well as how psychobiotics like Biotis GOS can reduce symptoms and feelings of anxiety.
“We developed Biotis to usher in a new era of ingredients science – one that responds directly to the key concerns of today’s consumers. Given the challenges of the last year, mental well-being, including anxiety, is one of the most pressing and widespread global health issues right now. We’re very proud to be playing our role in furthering scientific understanding of how prebiotics like galacto-oligosaccharides can target the microbiome to bring about benefits in mental wellbeing.”
Dr Kathrin Cohen Kadosh, Reader in Developmental Cognitive Neuroscience at the University of Surrey and Head of the Social Brain and Development Lab, said: “We have been able to show that a simple and safe food supplement including prebiotics can improve both the abundance of beneficial bacteria in the gut, and mental health and well-being in young women. This new research marks a significant step forward and opens up more opportunity to advance our understanding of the link between the gut microbiome and mental well-being.”
Source: Scientific Reports
Johnstone. N., et al
"Anxiolytic effects of a galacto‑oligosaccharides prebiotic in healthy females (18–25 years) with corresponding changes in gut bacterial composition"