A randomized, double-blind, crossover trial involving 42 healthy adults aged 45–75 years found that 4 weeks of soluble corn fiber (SCF; 18 g/day) supplementation improved aspects of cognitive performance and modified gut microbiota composition. SCF significantly reduced reaction times during both congruent and incongruent attentional inhibition tasks, indicating enhanced executive function. Supplementation also resulted in a nearly four-fold increase in Parabacteroides abundance and altered microbial carbohydrate metabolism pathways. Higher levels of fecal acetate and propionate were associated with faster cognitive responses, while moderation analyses suggested that cognitive benefits varied according to the extent of Parabacteroides enrichment. Additional analyses confirmed that Parabacteroides distasonis can ferment SCF. Although direct microbiota-mediated effects on cognition were not established, the findings suggest that SCF may support cognitive function, at least in part, through modulation of the gut microbiota and microbial fermentation activity.
Source : https://www.sciencedirect.com/science/article/pii/S0022316626001227?via%3Dihub
