Even though they've been around for years, it looks like "probiotics" are now the next new thing. Every time I pick up a journal or attend a seminar I'm bombarded with ads, literature, and sales reps hawking their particular brands. The newest buzz is around probiotics and depression. As usual, hype and hyperbole abound, but there is actually some growing evidence of an interrelationship between the gut and behavior. (Check out our most recent issue of ScienceInBrief.com) Here's some news that may give a bit of perspective.
Enter "psychobiotics", a new term defined as "a live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness." Timothy Dinan, lead author of Psychobiotics: a novel class of psychotropic, published in November's issue of Biological Psychiatry, states these bacteria are capable of delivering neuroactive substances (i.e. serotonin or GABA) which can affect mental health via the brain-gut axis. The authors cite evidence that certain types of intestinal flora may play a role in alleviating symptoms of depression and even chronic fatigue.
Exactly how the body develops imbalances of the intestinal flora isn't precisely known, but various theories such as early childhood stress and antibiotic therapies have been widely discussed to date. The one thing which seems likely at this point is that all "probiotics" will not be equal in terms of psychotropic effect. Dinan has been quoted as saying "What is clear at this point is that, of the large number of putative probiotics, only a small percentage have an impact on behavior and may qualify as psychobiotics."
For now...stay alert and don't believe everything the supplement reps are telling you! More data is definitely needed, but this is a hot topic and additional studies will almost certainly be coming down the pipe. This is a subject of considerable interest to chiropractors so we'll try to stay on top of it as things develop.
Author: Mark R Payne DC
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