Aim at the Gut, Hit the Brain?

Probiotics, which may improve overall functioning, are live organisms that alter the intestinal microbiome. In contrast, prebiotics are soluble nonliving fibers that stimulate beneficial intestinal bacteria. Investigators in Ireland studied whether the prebiotics fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS) might be effective in animal models of anxiety and depression.

Mice were given 3 weeks of supplementation with GOS, FOS, GOS plus FOS, or water and then were exposed to chronic social and other forms of stress. Compared with water, the prebiotics, especially their combination, altered the types and number of intestinal bacteria, with higher cecal concentrations of short-chain fatty acids. Paralleling these changes, the…