The COVID lockdown has shed a bright, shiny spotlight on one of the largest medical challenges we face as a community: mental health. The loneliness caused by social distancing mandates and the uncertainty of how the pandemic affects our short- and long-term personal and financial well-being, places additional burdens on many of those we care about who may be suffering from depression, anxiety and other mental disorders. While the pandemic may soon end, the despair expressed by many of our friends and family will likely take some time to subside. As such, we take great interest in knowing the latest medical research that may lead to things we can do to alleviate the pain and suffering of these disorders.
Typical treatment for many mental disorders includes is oral medication. Often the drugs prescribed are exact copies of the neurotransmitters that occur naturally within our bodies or compounds with closely related structures; the strategy is to adjust overall brain neurochemistry toward "normal" function in a very targeted way. Unfortunately, like any medication taken as a pill, a major challenge is to get enough of it to the intended site of action, which in this case, the receptors deep within the brain. Oral medications must be exceptionally robust considering that their biochemical journey begins by being swallowed and exposed to the stomach's chemically reactive cauldron of concentrated acid. The portion of the dose that survives the stomach intact must find its way to the lining of the digestive tract and stick to it long enough to be absorbed into the blood stream- the body's drug delivery highway. Along the way, some drug may undergo undesired metabolism by the enzymes and chemical agents within the blood stream and/or it may be eliminated from the body outright through normal renal and hepatic pathways. Invariable, a portion of the dose is simply "left behind" or distributed onto non-specific tissues and cells that it encounters as it makes its way to the brain. At the end of the day, if the initial dosing is too low, not enough compound will arrive to the brain to make a perceptible effect. Alternatively, if the dosing is too high, favorable effects we seek in solving one condition might easily be swamped by side effects caused by inadvertent drug interactions.
Our understanding of the importance of the role of the biome in human health is growing day by day. The enteric nervous system is a complex network of nerve bundles and sensory receptors that surrounds the gut and digestive organs. The density of this network rivals the central nervous system and brain itself in size and importance. This "second brain," is linked directly to our 'first" brain by a neuron-packed superhighway called the vagus nerve. Together, this system forms a "gut-brain axis" through which real-time status of the activities within the gut are passed along to our central nervous system which ultimately manages the unconscious and executive actions we take regarding our dietary- and other- behaviors. What is astonishing is that the microbes within our guts actually produce (secrete) a wide variety of psychoactive substances including many that are exact chemical matches to those that we prescribe as oral medications! As just one example, a recent study showed that gamma aminobutyric acid (GABA), an inhibitory neurotransmitter used to reduce signaling to the brain and serves to dampens anxiety and depression, is secreted by specific microbial strains within the biome in amounts that would be expected by a typical orally administered pill!
As discussed in a previous blog, Our Biome Told You To, switching out a particular diet with another is a natural and effective way to remodel the biome. But what biome should we strive for to address mental health issues? In April 2019, scientists of the Flemish Gut Project published the results of a comprehensive analysis of the gut microbiota of a group 1052 human subjects. As part of the study, each participant was asked to fill out a Quality of Life (QoL) survey to generate a mental health score; low QoL scores were consistent with depression and anxiety, while high scores were associated with normal mental health status. When the bacterial strains (which ones and how much) within each of the participants’ biome were compared to their QoL profiles, it was determined that those with the lowest QoL- those with symptoms of depression and anxiety-were deficient in 2 specific bacterial strains: Coprococcus and Dialister. DNA analyses of these two strains confirmed that they possessed the specified genetic machinery required to synthesize the mood-affecting neurotransmitter GABA. From a Citizen Scientist perspective, it is fair to hypothesize that the deficiency of Coprococcus and Dialister within the biome could mean that the levels of biome-produced neurotransmitters are low and may in turn be a contributing factor to the low QoL scores. Furthermore, is it reasonable to inquire whether it could possible to bio-hack our biome by adopting a diet that favors these potentially depression/anxiety-fighting microbial strains? The answer seems to be yes!
Consider the set of studies where researchers followed the changes in the gut biome (what strains and their percent composition) for subjects that were fed specified diets. In one study, a diet rich in barley and whole grain led to a biome that exhibited a higher prevalence of one of the deficient strains identified in the previous study: Dialister. Similarly, in another study, subjects were given a diet high in 3-omega rich foods such as salmon. The result: the new diet transformed the biome in a way that led to an increase in other deficient strain: Coprococcus.
What would happen if subjects were given a diet of both barley and fish? Would this lead to a biome fortified with sufficient Dialister and Coprococcus to produce higher concentrations of GABA, and would this dietary change alone be sufficient to case participants to alter low QoL scores upward in the Flemish study?
Of course, those with severe depression and/or anxiety should be encouraged to seek immediate professional guidance to help them through. But, rather than waiting for the definitive clinical trial and scientific verification, it seems that deliberately adding barely, whole grain wheat and fish to one’s diet seems like a safe and consequent-free way of bio-hacking the gut microbiota toward a very specific end. The Western Diet is implicated for the exponential increase in a number of diseases that pervade our society, including mental health disorders, so it is entirely logical that diet could also hold the cures.
