http://goo.gl/vvleik
Overall, research on probiotics and anxiety is still in its early stages. According to the authors, this is the first study to provide some extremely limited observational evidence for the efficacy of probiotic supplementation to fight, specifically, social anxiety, and thus, they did not mean to infer causality. Regardless, due to several limitations imposed by the study design, and the huge number of possible confounding variables, this study should solely serve as preliminary evidence, especially considering how strong of a confounding variable exercise is, as several papers have demonstrated its anxiolytic effects. However, if further well-conducted RCTs can suggest a causal role, independent of exercise and other possible confounding variables, probiotics or fermented foods consumption could potentially serve as great low-risk supplement to traditional treatment for social anxiety.