Unpasteurised milk and dairy products intake could potentially alter gut microbiome composition which may influence psychological functioning.
In this observational study, the impact of dietary change involving unpasteurized dairy consumption on gut microbiota and psychological state was observed among participants of a 12-week residential cookery course on an organic farm. Twenty-four participants, who primarily consumed food from the farm including unpasteurised milk and dairy products, provided faecal samples at the beginning and end of the course. Concurrently, they completed self-report questionnaires touching on mood, anxiety, and sleep aspects and nutrient intake was monitored via a food frequency questionnaire. Gut microbiota analysis was carried out using 16S rRNA gene sequencing and measurement of faecal short chain fatty acids.
Post-course, there was a significant growth in the relative abundance of a specific bacterial genus in the gut, associated with unpasteurised milk and dairy product intake. Furthermore, an increase in a particular faecal short chain fatty acid, valerate, was observed together with an elevation in the functional richness of the microbiome profile. The latter was determined by measuring the predicted neuroactive potential using a unique gut-brain module approach. Despite safety concerns, the consumption of unpasteurised milk and dairy products seemed to promote the growth of probiotic bacterial genus, known to be beneficial for various physical and mental health outcomes.
