Intake of Lactiplantibacillus plantarum HEAL9 Improves Cognition in Moderately Stressed Subjects: A Randomized...

The usage of probiotics has expanded beyond the areas of gut and immune health improvement. Several studies have shown the positive impact associated between probiotics and stress, cognition, and mood; a relationship referred to as the gut-brain axis.

The aim of this exploratory study was to evaluate the effect of the probiotic strain Lactiplantibacillus plantarum HEAL9 (LPHEAL9) on the gut-brain axis in subjects with moderate stress. One hundred and twenty-nine subjects aged 21-52 years completed the study, randomized to consume either LPHEAL9 (n = 65) or placebo (n = 64) for 12 weeks.

Perceived stress and awakening cortisol were significantly reduced over time in both groups. A significant improvement in four cognition tests after consumption of LPHEAL9 compared to placebo was observed (rapid information processing test, numeric working memory test, paired associated learning, and word recall, p < 0.05). There was a tendency for a significantly better improvement in the LPHEAL9 group for three mood subscales (Confusion-Bewilderment, Anger-Hostility, and Depression-Dejection) and for fewer subjects with poor sleep in the LPHEAL9 group compared to placebo (p < 0.10).

Intake of LPHEAL9 significantly improved cognitive functions compared to the placebo, potentially by ameliorating aspects of mood and sleep.