Research is supporting the idea that eating a balanced diet and promoting gut health can optimise brain function and mood.
Nutrition plays a vital role in achieving optimal well-being and improved quality of life but how much is linked to the health of the bacteria in your gut?
To date the effects are not well understood, so Defence Science and Technology Group cognitive neuroscientist Dr Diane Pomeroy and colleagues joined forces with Flinders University health scientists, Professor of Psychology Eva Kemps and her Honours student Reneshree Govender, to set about answering that question.
“An emerging area of research interest in the field of supplements is synbiotics,” Ms Govender told delegates at the 2017 Defence Human Sciences Symposium.
“Synbiotics are a combination of pre- and probiotics that improve the survival of the probiotics, helping them to remain embedded in the gut and enhancing the changes to the gut microbiota.
“Our study investigated the effects of prebiotic and probiotic supplements given in a synergistic combination on human cognition, well-being and mood.”
Dietary supplements such as probiotics are increasingly used to augment gut bacteria in our fast-paced, antiseptic Western world.
Probiotics are beneficial gut bacteria commonly found in foods such as yoghurt, sauerkraut and kefir. These bacteria can nurture the naturally occurring gut microbiota.
Prebiotics are non-digestible carbohydrate fibres, commonly found in fruits, vegetables and legumes. Prebiotics promote the growth and survival of the probiotic.
There’s increasing evidence that they are helpful for maintaining a healthy human gut, but does ingesting sufficient quantities have a beneficial effect on cognitive function, well-being or mood?
This study was, to the team’s knowledge, the first to investigate the direct effects of prebiotic and probiotic supplements on human cognition and mood.
They also investigated whether there was any indirect effect on cognitive function from mood improvement, because earlier research has shown what we all know from personal experience – that a negative mood affects thinking.
Thirty carefully-selected Flinders University students were involved in various tests, before and after supplementation with synbiotics.
The participants ingested 5 grams of synbiotic powder every day for 28 days.
“The battery of cognitive tests assessed immediate, delayed and recognition memory; working memory; attention and vigilance; ability to ignore distractions; inhibitory control; and speed of processing,” Dr Pomeroy says. “Participants also completed a mood measure that assessed depression, anxiety and stress.”
The testing included, for example, providing participants with a 15 noun word-list and later asking them to recall as many words as possible from the list.
Reneshree says preliminary results show a significant improvement in those participants who had taken supplements, in terms of immediate memory and delayed memory, compared to those who had taken the placebo.
“However we didn’t find significant improvements for recognition or working memory, or mood (depression, anxiety and stress). For attention and vigilance aspects, our analysis has thus far found moderate effects,” she says.
“Taken together, this was the first study to demonstrate that prebiotic and probiotic supplements do improve immediate and delayed memory in healthy, young adults.
“Our study has implications for the influence of synbiotics on gut-to-brain access, as a potential mechanism by which cognition can be enhanced.
“Such supplements could be particularly useful for workers prone to high levels of stress including Army personnel. We believe we’ve come up with promising first steps into discovering the potential, and further investigation is warranted.”
Reneshree was given the Leone Warne Award for Best Oral Presentation after outlining the research preliminary results at the Defence Human Sciences Symposium (DHSS) 2017, held on 6-7 November.
The team’s paper “Effects of priobiotic+prebiotic supplementation on cognition, mental well-being and mood” (Reneshree Govender, Eva Kemps, Katie Tooley, Diane Pomeroy and Bianka Probert) won the DHSS 2017 Best Paper Award.
Professor Kemps also presented on “Dietary supplements and cognitive enhancement: A systematic review.”
The symposium promotes the outcomes of the Human Performance Research Network, established by DST Group and the Australian Army to enhance the performance of Australia’s military personnel. Universities and research groups around Australia are providing cross-disciplinary expertise to enhance solders’ performance, physically and cognitively.