Lactobacillus reuteri is an endlessly fascinating microorganism that can inhabit the human intestinal tract. This is the bacterial species we have been cultivating in our L. reuteri yogurt using the two strains, ATCC PTA 6475 and DSM 17938, that boost hypothalamic release of oxytocin and thereby smooths skin wrinkles, accelerates healing, turns off appetite, builds muscle, preserves bone density, and yields other spectacularly beneficial effects.
Animals such as pigs, mice, dogs, sheep, cows, and birds have abundant quantities of L. reuteri (of various strains) in their guts, but only 4% of modern humans have it, i.e., less than 1 in 20 people have L. reuteri among the thousands of species in their intestinal tracts and have them in small numbers. In other words, most modern people do not have this wonderfully beneficial microorganism and, if they do, have them in relatively small numbers.
Curiously, the discoverer of L. reuteri, Dr. Gerhard Reuter, observed that this species was much more common in humans during the mid-twentieth century, its prevalence in humans having dwindled over the last 50 years for unclear reasons. (You and I can easily speculate, however, that the onslaught of microbiome-disrupting factors in modern life have likely played a role.) L reuteri must therefore be among the species more susceptible to the disruptions of modern life.
Recall that, not only is L. reuteri a potent provocateur of vagal nerve-mediated hypothalamic release of oxytocin, but it also plays an important probiotic role in the upper gastrointestinal tract, unlike nearly all other microorganisms that preferentially colonize the colon, i.e., the lower gastrointestinal tract. L. reuteri may therefore play an important role in preventing or suppressing small intestinal bacterial overgrowth, as well as H. pylori that causes stomach and duodenal ulcers along with a long list of other health conditions. SIBO, in which unhealthy bacterial species have ascended up the length of the gastrointestinal tract, a situation associated with fibromyalgia, restless leg syndrome, irritable bowel syndrome, and other common conditions, is now an epidemic on a par with that of obesity and overweight.
How much has this and other shifts in microbial populations played a role in encouraging type 2 diabetes, obesity, overeating, autoimmune conditions, etc., i.e., health conditions that are wildly out-of-control in the U.S.? Given the oxytocin-stimulating effects of L. reuteri that cultivate empathy and connectedness to the people around you, now largely gone in 96% of people, could the disappearance of L. reuteri underlie some of the social changes we have witnessed in modern times such as isolation and gun violence? We can only speculate, as there is no way to confidently connect a cause-effect relationship.
Bottom line: Make the L. reuteri yogurt and enjoy all the age-reversing, health-restoring benefits it provides. Then share with others, show them how to make it themselves. Maybe you and I will help make this world a better, safer place, too.