Probiotics are widely known as “friendly bacteria” that help maintain a healthy digestive system. They also boost immunity, and many healthcare practitioners recommend you have them daily. (When buying supplements, choose brands that have from 50 billion to 450 billion flora per dose.) Now researchers think some probiotics can also improve mental health–and they have come up with a new term for them: psychobiotics.
A review article that was published online in the June 2013 issue of Biological Psychiatry says psychobiotics are “a live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness,” specifically depression or other stress-related disorders.
According to Alan C. Logan, a Connecticut-based naturopathic doctor and co-author of Your Brain on Nature, probiotics help to balance gut microbiota–the bacteria inside our stomach. “These bacteria do a lot but, most importantly, they protect the gut lining,” he says. An imbalance of gut microbiota (due to psychological stress or a high-fat, high-sugar diet, for example) can lead to intestinal permeability. Why is that a bad thing? Because it means parts of the bacteria could pass through the gut lining and into your bloodstream, leading to low-grade inflammation. And that has been connected with obesity, disease–and mental health problems.
The beneficial probiotic strains, and those that are typically found in foods, are members of the lactobacillus and bifidobacterium families, says Logan. A 2011 study published in the British Journal of Nutrition monitored adults who were given either a probiotic product that included lactobacillus and bifidobacteria, or a placebo, every day at breakfast for 30 days. Those who consumed probiotics were found to have lowered stress and anxiety. The study concluded that “gut microflora play a role in stress, anxiety and depression,” and that probiotics may be useful as adjunct therapies in psychiatric disorders.
It may be unrealistic to expect that probiotics will replace medications in the treatment of depression. But the message for now is that probiotics not only help you avoid obesity and disease–in Logan’s opinion, “although more research is needed, probiotics taken in conjunction with a healthy diet and exercise may benefit mental health.”
Foods with good bacteria
“Fermented foods provide good bacteria to our guts,” says registered dietitian and BH contributor Sue Mah. “Plus, it may be easier for our bodies to absorb nutrients from fermented foods.” Aim for one to two servings of these foods every day. “Without regular intake, probiotics do not survive in the colon for more than one or two weeks,” says Mah. Here are some choices:
• Kombucha tea