This placebo-controlled, double-blinded, and randomized study involved 169 participants between the ages of 52-75 years old who were put into two groups; those with no neurological issues and those with mild cognitive impairment, and the participants were given either a placebo or LGG probiotic for three months.
Lactobacillus rhamnosus GG (LGG) probiotics were selected due to prior research indicating potential beneficial effects. 16S rRNA gene sequencing was used to identify and compare bacteria presence in stool samples, and whole genome sequencing was used to gain insights into the functional roles of the bacteria(s) identified.
“The implication of this finding is quite exciting, as it means that modifying the gut microbiome through probiotics could potentially be a strategy to improve cognitive performance, particularly in individuals with mild cognitive impairment,” said Mashael Aljumaah, a microbiology doctoral candidate at the University of North Carolina at Chapel Hill and North Carolina State University. “This adds a new layer to our understanding of the microbiome brain-gut connection and opens up new avenues for combating cognitive decline associated with aging.”
According to the researchers, their analysis revealed that the genus Prevotella was found in higher levels among those with mild cognitive impairment compared to those with no impairment, suggesting that gut microbiome composition could be an early indicator for mild cognitive impairment and offer an opportunity for earlier intervention.
Those with mild cognitive impairment who receive the probiotics were found to have had their levels of Prevotella decrease, and this change coincided with improved scores during cognitive testing. Suggesting that cognitive health among older adults may be improved by manipulating gut microbiota.
“Many studies focus on severe forms of cognitive diseases such as Alzheimer’s and dementia, but these conditions are more advanced, making them significantly harder to reverse or treat,” said Aljumaah. “In contrast, we focused on mild cognitive impairment, which can include problems with memory, language, or judgment. Interventions at this stage of cognitive impairment could slow down or prevent the progression to more severe forms of dementia.”
“By identifying specific shifts in the gut microbiome associated with mild cognitive impairment, we’re exploring a new frontier in preventive strategies in cognitive health,” said Aljumaah. “If these findings are replicated in future studies, it suggests the feasibility of using gut microbiome-targeted strategies as a novel approach to support cognitive health.”
