Ready for a paradigm shift? Some very interesting studies have emerged recently highlighting the value that probiotics–foods or supplements rich in live bacteria–may hold for those of us suffering from depression, anxiety, and even dementia. In a small study from Holland’s Leiden Institute for Brain and Cognition, women who took a probiotic supplement designed to enhance gut bacterial diversity experienced less reactivity to sad thoughts than those who took a placebo.
Resilience to sad thoughts is a sign of strong mental health. For example, in depressed people, a sad stimulus can turn an otherwise spotless sky into an overcast day, whereas someone with a healthy mood can simply observe the sad thought and move on, without significant cloud formation. Can consuming more fermented foods, like kombucha, yogurt, sauerkraut, and kimchi help our anxiety? Maybe, according to another study that found that students who consumed more of these types of foods had less social anxiety.
The effect was especially strong in those who had neurotic personalities. “It is likely that the probiotics in the fermented foods are favorably changing the environment in the gut, and changes in the gut in turn influence social anxiety,” wrote one of the authors in the College of William and Mary and University of Maryland study.
Groundbreaking research out of Iran suggests that probiotics may even boost cognitive function in one particularly desperate group: patients with advanced Alzheimer’s. The researchers put severely demented patients on a twelve-week, high-dose cocktail of Lactobacillus and Bifidobacterium (two common strains of probiotics) and found that, compared to the control group who received only a placebo, the probiotic group improved on a test of cognitive function by an astonishing 30 percent.
Though the effect would need to be replicated with a larger sample size, these preliminary results are certainly cause for hope. Scientists have truly just scratched the surface of what will be a fascinating decade to come in microbiome research as the broad reach of probiotics comes into view. Certain strains may help fight off certain cancers, boost heart health, enhance brain neurogenesis, and even alter mood states–the latter paving way for “psychobiotics” (more on this in chapter 8). 36