I just found an article[i] in Scientific American describing a study in which the probiotic bacteria, Lactobacillus reuteri (derived from human breast milk), is being used to treat post-traumatic stress disorder (PTSD). 40 veterans suffering from PTSD are in a clinical trial in which half are given the probiotic to drink, half are controls and given a placebo. After 8 weeks, the vets are to be tested by having to give a speech in front of a group, while the researchers test their stress levels. They will also have their blood and stool checked for signs of inflammation and changes to their microbiome. (The results will be released in a year. I’ll keep an eye out and report back then!)
This particular bacteria was selected because, in a recent animal model study, a similar organism (however, one that is not yet approved for use in humans) had a profound effect on anxiety and fear behaviors. Both the organism used in this mouse study, as well its relative, L.reuteri, cause the body to produce more of an enzyme that is critical in the production of serotonin – which (as shown by the use of drugs like Prozac), is calming and anti-depressive.
About a year ago, I first read about L.retueri in a study[ii] looking at autism, using an animal model. The absence of this species in mice causes marked social deficits. Adding it back into their guts led to a reversal of some of these social abnormalities. The researchers noted that animals born to mothers who had been fed a high-fat diet (equivalent to eating fast-food 3X per day) had dramatically altered microbiomes and behavior – but that housing these babies with normal animals caused reversal of the behavioral and biome abnormalities. They were able to isolate the major difference and found that L.reuteri “…was reduced nine-fold in the microbiomes of the mice born to mothers on the high-fat diet.”
By feeding the offspring this particular organism, the researchers were able to “rescue their social behavior.” They noted too that the L.reuteri “…promoted the production of the ‘bonding hormone’ oxytocin, which is known to play a crucial role in social behavior and has been associated with autism in humans.”
A quick Google search confirmed what I suspected: yes, oxytocin is being tested for treatment of PTSD and so far, has been shown[iii] – at the very least –to improve feelings of compassion in those afflicted. And note too that serotonin abnormalities have been studied in autism for a long time. More than that, high levels of sympathetic nervous system hormones (stress hormones) are high in children on the spectrum.
True to my philosophy, “If it can’t hurt and it could help, do it,” I just started giving my son, Alex, homemade yogurt made with L.reuteri. I mean…why not?!