A study of 98 people in Xinjiang, China, published Oct. 23, 2026, in Psychoneuroendocrinology, found mild but consistent differences in the functions of gut bacteria in people with major depression, including pathways for short-chain fatty acids.
A review of fourteen studies in adults aged 60 or older found that probiotics, prebiotics and synbiotics improved global cognition scores by 1.28 points in a pooled subgroup, though the studies were few and varied.
A review published Oct. 29, 2026, in The Lancet explains irritable bowel syndrome and related gut-brain disorders, which affect 20% of the world's population, and what helps: education, diet, fiber, targeted drugs and psychological therapies.