Links have been made between gut health and depression, anxiety, stress, even sleep. A recent study tested this relationship in mice, which provide a very useful model of our own digestive and nervous system. The study found that treatment with a lactic acid producing strain of probiotic may help to reduce stress as well as depression and anxiety. The lactic acid producing bacteria "induced region-dependent alterations in GABAB1b mRNA in the brain with increases in cortical regions (cingulate and prelimbic) and concomitant reductions in expression in the hippocampus, amygdala, and locus coeruleus, in comparison with control-fed mice" and more importantly, "reduced stress-induced corticosterone and anxiety- and depression-related behavior" (Bravo, 2011).
Ongoing research is investigating whether gut bacteria are one reason for the mood symptoms in medical conditions.
Legere Pharmaceuticals carries a unique room temperature stable lactic-acid producing probiotic known as Bi-ProZyme to help replenish healthy bacteria contributing to better health.
Bravo, J., Paul, F., Chew, M., Escaravage, E., et. al. (2011). Ingestion of Lactobacillus strain regulates emotional behavior... PNAS. Retrieved from: http://www.pnas.org/content/108/38/16050