by Derek Beres
on a supermarket shelf July 30, 2007 in Berlin, Germany.
German milk producers have announced
they will raise prices on milk and dairy products
starting July 31 nationwide by as much as 50%.
(Photo by Sean Ga)
With all the advancements being made in neuroscience, the complexities of digestion have not been well understood, the dark matter of our body's galaxy.
That is changing,
There are also more immune cells inside of our stomachs than in blood and bone marrow, which makes what we put into our mouths so important.
Our diets might affect our brains more than the other way around.
As Emeran Mayer puts it,
Humans are collectively experiencing increased rates of anxiety, which is now the planet's most pervasive psychological disorder.
Increased stress has numerous destructive tendencies in our guts, including the alteration of contractions, transit rates between our stomach and large intestine, and blood flow.
When that blood is transporting extra cortisol due to an increase in our corticotropin-releasing factor (CRF), the result is increased storage of visceral fat, decreased function of our immune system, and, of course, anxiety.
While there are a number of means for altering your gut environment - a healthier diet with less sugar; stress-reducing techniques like meditation; regular exercise; therapy - one of the most prominent is the intake of probiotics, as new research (Efficacy of Probiotics on Anxiety - A Meta-analysis of Randomized Controlled Trials) published in Neuropsychiatry (London) shows.
Our guts are filled with microbes. I remember my high school biology teacher trying to gross us out by informing us that if she were to zap us so that only living microorganisms would remain, a few pounds would end up next to each of our desks.
Turns our these critters are necessary for survival; how we treat them affects how they treat us.
Probiotics are, in the words of the World Health Organization,
In 2010 the organization began developing guidelines for probiotics in food, which is tricky for a number of reasons.
There's a world of difference between refrigerated and room temperature probiotics, one that extends well beyond price.
Yet this barely-regulated industry is difficult to navigate. Stated benefits exceed actual benefits, as often happens with medicine masquerading as nutritional supplements.
The research team above, led by Ruixue Huang at the Xiangya School of Public Health in Hunan, China, searched seven academic databases and chose ten studies that showed probiotics' efficacy in reducing anxiety.
Importantly, the team recognizes crosstalk between gut and brain:
The team had been searching for a meta-analysis on probiotics and anxiety disorders, which they were unable to find.
Their requirements included studies on human subjects with anxiety disorders, a variety of probiotic sources (fermented yogurt; powders; oil suspensions; capsules), and studies from unique test groups, to avoid overlap.
They did not include studies on mice and rats, case reports, or incomplete data.
Huang's team collected research from,
...all of which showed beneficial effects from a variety of probiotics, including popular and readily available strains such as Lactobacillus acidophilus and Lactobacillus casei.
A total of 660 human subjects were included in their final results:
As Mayer concludes in his book, however, there is no "one-size fits all recommendation" for probiotics.
So while probiotics might not cure your anxiety in one shot, they can play an important role in the process.
Understanding strains and dosage is an exciting field of research that is certain to yield critical advancements in the near future.