Speaking to NutraIngredients, Dr Harriët Schellekens presents a convincing case of the gut-brain axis’ role in shaping host appetite and eating behaviour, linking these elements to stress and mood.
“We know our diet is one of the biggest determinants for the microbiota ‘health’, diversity and composition,” says Dr Schellekens, lecturer at University College Cork and funded investigator at the APC Microbiome Ireland.
“A diverse microbiota is a healthy microbiota,” she adds “But we do not yet know if our microbiota can also influence the way we perceive foods and if they can influence food choice and food motivation & reward.
“This is what I am keen to further investigate, the microbiota at the interface of food and mood.”
Dr Schellekens’ scheduled appearance at this year’s Probiota in Dublin will discuss her latest research as well as her thoughts on how modern living impacts the delicate nature of the gut microbiota.
She points to the problem of not eating a diverse range of foods, especially the insufficient intake of dietary fibre.
“You have to keep your microbes in mind with your food choices,” Dr Schellekens says. “A diverse range of healthy, whole unprocessed foods will yield a diverse gut microbiota which is considered to be a healthy one.
“Dietary fibre acts as a prebiotic and will stimulate proliferation of good bacteria. A lack of diversity of gut bacteria will decrease how well you recovery from harmful conditions, including gastrointestinal infection and following antibiotics.
While alcohol is linked to a healthy gut flora, Dr Schellekens is not entirely convinced commenting that moderate red wine consumption’s beneficial effects on gut bacteria is due to its polyphenol content.
“Drinking too much alcohol can also wreak havoc on your gut flora,” she adds. “Red wine, as do all fermented foods, contains a lot of histamine which can also give you gastrointestinal discomfort and even allergic rhinitis.”
A ‘food-first approach’
With research focusing on the gut modifying-abilities of probiotics and prebiotics, a ‘food-first approach’ appears to have been somewhat overshadowed by their potential and convenience.
The rapidly evolving universe of probiotics, prebiotics and the microbiome will be propelled into the new decade at the upcoming Probiota 2020 summit in Dublin on February 10-12.
From advances in microbiome research, to start-ups, key market stats, crucial clinical science and regulatory knowledge, attendance is a must-have for those in the prebiotic, probiotic and microbiome sectors.
But Dr Schellekens thinks it’d be premature to dismiss this approach, pointing out that prebiotics and probiotics can be found in everyday foods.
“I think a ‘food-first approach’ is valid,” she says. “Hippocrates said let food be thy medicine and medicine be thy food.
“I also think probiotics should be taken with caution; there needs to be a valid reason, don’t take if there is no need. Fix food, add prebiotic rich foods, then probiotics.”
Dr Schellekens dismisses the notion of a danger that consumers may use food as the only treatment for mood or as a way to ‘eat’ their way out of feeling depressed or anxious.
“Common sense applies. There is a need for medication this avenue cannot be ruled out,” she says.
“Severe depression cannot be ‘cured’ by food alone and medication has proven efficacy. But a better diet can certainly help. Afterall we need to provide microbes with their optimal foods (prebiotcs) also.”
Antibiotic and pharmaceuticals
Other aspects of modern living that influence the microbiota’s functioning include stress, insufficient sleep and antibiotics, all of which can negatively affect the diversity of a host’s microbes.
The increase of antibiotic and general pharmaceuticals in the population, is giving researchers a cause for concern as evidence suggests common drugs — from antibiotics to antidepressants —could disrupt the delicate balance of bacterial populations.
Indeed, this issue will form a pillar of Dr Schellekens’ presentation at Probiota, entitled: ‘A Microbiome Menu: The microbiota-gut-brain axis at the interface of appetite, food and mood.’
However, Dr Schellekens’ draws on her research to discuss a targeted pharmaceutical approach used to gain mechanistic insight into gut bacteria-derived metabolites.
These metabolites are strongly suspected as modulators of GPCR and neuroendocrine signalling within the gut-brain axis.
These metabolites are often an overlooked aspect to microbiome research with Dr Schellekens commenting on their potential role in the circadian rhythms and sleep.
“Many studies are showing that microbes can secrete mimetics of endogenous ligands and even neuroactives.
“Evidence is also showing that brain and behaviour are influenced by the microbiota. Future studies will show the indirect and direct mechanism, likely to involve these microbiota-derived metabolites.”