Across 4 studies, all reported beneficial effects of Bifidobacterium bifidum Rosell-71 on depressive symptoms, with effect sizes ranging from small to moderate. Evidence is drawn primarily from systematic reviews and reviews, including one large systematic review (n=3,353) showing moderate benefits; no specific dose or form data were consistently reported across studies.
Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Evidence base is small (only 4 studies) — conclusions should be considered preliminary.
There was a notably high measurement of effectiveness specifically in the treatment of depression symptoms.
Lactobacillus plantarum ... demonstrated particularly promising effects ... Psychobiotics show significant potential as adjunctive and therapeutic agents in depressive disorders through modulation of the gut-brain axis.
all demonstrating a significant amelioration of depression status after probiotic/psychobiotic treatment... In total, 7 out of 10 studies with probiotics as an add-on therapy ... exhibited a significant amelioration of depression status against placebo treatment.
This review explores the emerging field of hiPSCs and their potential in advancing microbiota-gut-brain axis science and depression research.