Normally we think of probiotics for our gut. In a double blind, placebo controlled study, two probiotic strains, Lactobacillus helviticus and Bifidobacter longum were shown to lower levels of anxiety. These probiotics were shown to increase the number of GABA receptors, which induce relaxation, in the brain. They also reduce gut inflammation.
Mental health is not just about your brain; it is also about your gut!