Researchers are beginning to learn more about how probiotics can be used to treat mental health issues, with a new study showing that a combination of 14 bacterial strains eased symptoms of anxiety and depression.
Probiotics are health-promoting live bacteria and yeast that live in the human body. We can also consume them through supplements and fermented foods.
Despite links between bacterial imbalances and depression, research hadn’t found that probiotic treatments are effective against depression before, though studies usually tested only a single strain of bacteria.
This pilot study, however, opens the door for larger studies exploring the use of multi-strain supplements for mental health. The combination included different strains of Bifidobacteria and Lactobacillus, in addition to Lactococcus lactis and Streptococcus thermophilus, taken in a proprietary blend.
All subjects were between 18 and 55, had major depressive disorder, and were taking an antidepressant that wasn’t fully resolving their symptoms. Patients received either the 14-strain probiotic or a placebo.
Study Specifics
On average, those taking the probiotics—24 of 49 patients—experienced a reduction of one severity grade on two depression rating scales. Patients had even greater relief from anxiety, which is a comorbid condition in up to half of patients with depression. In fact, researchers hinted that a reduction in physical anxiety symptoms could be the driving factor for lessening depression.The multi-strain probiotic contained 8 billion colony-forming units. Patients took either the probiotic or the placebo daily for eight weeks, in addition to regular antidepressant medication.
Medication Doesn’t Work Well
If future studies find effective blends of probiotics to treat various mental health issues, millions of people could receive some much-needed help.However, hopes that probiotics could resolve depression may be inflated, according to Dr. James Greenblatt, a psychiatrist, author, and international lecturer on the role of nutrition in mental health.
“I don’t think everyone going out and taking probiotics is going to solve depression being the No. 1 cause of global disability worldwide,” Dr. Greenblatt said. “But the relationship between gut health and depression is real.”
Dr. Greenblatt told The Epoch Times that those in the field of functional psychiatry aren’t sure how exactly the microbiome—all the bacteria, fungi, and viruses living in and on humans—plays a role in brain function. However, both animal and human studies reveal an association.
Anyone interested in trying a probiotic for depression should ask a health care provider whether there’s research specific to what probiotic they are considering, Dr. Chris Palmer, a psychiatrist, told The Epoch Times.
Possible Mechanism of Action
However, research needs to continue testing probiotics because more therapies for depression are desperately needed, according to the authors of a meta-analysis of probiotic studies for depression published earlier this year in the International Journal of Molecular Sciences.Although our gut microbes don’t directly produce BDNF, they do produce short-chain fatty acids (SCFA) that play a role in the production of BDNF.
Pinpointing this mechanism of action is meaningful progress that could help researchers determine which probiotics could be used to spur SCFA production.
The study pointed out that people suffering from depression have significantly lower levels of BDNF than healthy people. SCFAs are also associated with the integrity of the intestinal barrier, which protects the body from inflammation.
Microbiome and Oxidative Stress
Researchers have also established a link between oxidative stress and the types and numbers of microbes that form in the gut.“Oxidative stress is related to various human diseases, which covers depression,” the International Journal of Molecular Sciences meta-analysis notes.
Improving Gut Health Through Diet
Early studies showed that probiotics can be beneficial in certain people with psychosis, bipolar disorder, ADHD, and schizophrenia, Dr. Greenblatt said. He added that usually, increasing probiotics becomes part of a comprehensive lifestyle and treatment plan in a functional approach.“Most cultures have wide ranges of fermented foods that seed your gut bacteria. The traditional American diet doesn’t have much fermented food,” he said.
Functional psychiatrists are likely to focus on sleep, hormone adjustments, environmental factors, and diet, Dr. Greenblatt said. The microbiome is associated with all of these, though the relationship isn’t particularly well understood.
“The most direct impact of bacteria in our gut is diet,“ he said. ”Dietary change will be important. Changing your diet will change your gut.”