If You Can’t Beat Depression,
This Could Be Why.
Researchers examined the performance of germ-free mice,
which lack gut bacteria, on a kind of maze used to test anxiety-like behaviours. The maze is in the shape of a
plus with two open and two closed arms; normally, mice will avoid open spaces to minimize the risk of being seen
Normal mice, as expected, spent far more time in the closed
arms when placed in the maze. The germ-free mice, however, entered the open arms far more often, spending
significantly more time there than in the closed arms.
According to the study in Neurogastroenterology &
Motility, when they examined the animals' brains, they found that:
differences in behaviour were accompanied by alterations in the expression levels of several genes in the
germ-free mice. ... Bacteria colonize the gut in the days following birth, during a sensitive period of brain
development, and apparently influence behaviour by inducing changes in the expression of certain
Neurogastroenterology & Motility March 2011;
Most people fail to realize that your gut is quite
literally your second brain, and actually has the ability to significantly influence your:
So while modern psychiatry still falsely claims that
psychological problems such as depression are caused by a chemical imbalance in your brain, researchers keep
finding that depression and a variety of behavioural problems actually appear to be linked to an imbalance of
bacteria in your gut!
Germ-Free Mice Engage in High-Risk
In the featured study published last month in
Neurogastroenterology & Motility, mice that lack gut bacteria were found to behave differently from
normal mice, engaging in what would be referred to as "high-risk behaviour." This altered behaviour was
accompanied by neurochemical changes in the mouse brain.
According to the authors, microbiota (your gut flora) may
play a role in the communication between your gut and your brain, and:
"Acquisition of intestinal microbiota in the immediate
postnatal period has a defining impact on the development and function of the gastrointestinal, immune,
neuroendocrine and metabolic systems. For example, the presence of gut micro biota regulates
the set point for hypothalamic-pituitary-adrenal (HPA) axis activity."
The neurotransmitter serotonin activates your
hypothalamic-pituitary-adrenal axis by stimulating certain serotonin receptors in your brain.
Additionally, neurotransmitters like serotonin can also be found in your gut. In fact, the greatest
concentration of serotonin, which is involved in mood control, depression and aggression, is found in your
intestines, not your brain!
So it actually makes perfect sense to nourish your gut
flora for optimal serotonin function as it can have a profound impact on your mood, psychological health, and
The authors concluded that:
"[T]he presence or absence of conventional intestinal
micro biota influences the development of behaviour..."
This conclusion adds support to another recent animal study, which also
found that gut bacteria may influence mammalian early brain development and behaviour. But that's not all. They
also discovered that the absence or presence of gut microorganisms during infancy permanently alters gene
Through gene profiling, they were able to discern that
absence of gut bacteria altered genes and signalling pathways involved in learning, memory, and motor control.
This suggests that gut bacteria is closely tied to early brain development and subsequent behaviour. These
behavioural changes could be reversed as long as the mice were exposed to normal microorganisms early in life.
But once the germ-free mice had reached adulthood, colonizing them with bacteria did not influence their
According to Dr. Rochellys Diaz Heijtz, lead author of the
"The data suggests that there is a critical period early
in life when gut microorganisms affect the brain and change the behaviour in later
In a similar way, probiotics have also been found to
influence the activity of hundreds of
your genes, helping them to express in a positive, disease-fighting manner.
When you consider the fact that the gut-brain connection is
recognized as a basic tenet of physiology and medicine, and that there's no shortage of evidence of
gastrointestinal involvement in a variety of neurological diseases, it's easy to see how the balance of gut
bacteria can play a significant role in your psychology and behaviour as well.
With this in mind, it should also be crystal clear that
nourishing your gut flora is extremely important, from cradle to grave, because in a very real sense you have
two brains, one inside your skull and one in your gut, and each needs its own vital
Interestingly, these two organs are actually created out of
the same type of tissue. During foetal development, one part turns into your central nervous system while the
other develops into your enteric nervous system. These two systems are connected via the vagus nerve, the tenth
cranial nerve that runs from your brain stem down to your abdomen. This is what connects your two brains
together, and explains such phenomena as getting butterflies in your stomach when you're nervous, for example.
(For an interesting and well-written layman's explanation of this connection, read through
Sandra Blakeslee's 1996 New York Times
article Complex and Hidden Brain in Gut Makes Stomach aches and Butterflies.)
Your gut and brain work in tandem, each influencing the
other. This is why your intestinal health can have such a profound influence on your mental health, and vice
As a result, it should be obvious that your diet is closely
linked to your mental health. Furthermore, it's requires almost no stretch of the imagination to see how lack of
nutrition can have an adverse effect on your mood and subsequently your behaviour.
Have We Become Too Sanitized for Our
published last year in the Archives of
General Psychiatry reviewed the evidence for signs that psychiatric problems might be caused by lack of
natural microorganisms in soil, food, and the gut. And it did find such a link.
Rates of depression in younger people have steadily grown
to outnumber rates of depression in the older populations, and one reason for this could be the lack of exposure
to bacteria, both outside and inside your body.
Quite simply, modern society may have gotten too sanitized
and pasteurized for our own good.
Fermented foods have been traditional staples in most
cultures, but modern food manufacturing, with its focus on killing ALL bacteria in the name of food safety, has
eliminated most of these foods. You can still find traditionally fermented foods like
natto or kefir, but they're not the dietary staples they once used to be, and many people don't like them when
trying them out for the first time in adulthood.
When you deprive your child of all this bacteria, her
immune system—which is her primary defence system against inflammation—actually gets weaker, not stronger. And
higher levels of inflammation are not only a hallmark of heart disease and diabetes, but also of
The authors explain it as
"Significant data suggest that a variety of
microorganisms (frequently referred to as the "old friends") were tasked by co-evolutionary processes with
training the human immune system to tolerate a wide array of non-threatening but potentially pro-inflammatory
stimuli. Lacking such immune training, vulnerable individuals in the modern world are at significantly increased
risk of mounting inappropriate inflammatory attacks on harmless environmental antigens (leading to asthma),
benign food contents and commensals in the gut (leading to inflammatory bowel disease), or self-antigens
(leading to any of a host of autoimmune diseases).
Loss of exposure to the old friends may promote major
depression by increasing background levels of depressogenic cytokines and may predispose vulnerable individuals
in industrialized societies to mount inappropriately aggressive inflammatory responses to psychosocial
stressors, again leading to increased rates of depression.
… Measured exposure to the old friends or their antigens
may offer promise for the prevention and treatment of major depression in modern industrialized
Researchers World-wide have Linked Gut
Problems to Brain Disorders
Brain disorders can take many forms, one of which is
autism. In this particular area you can again find compelling evidence of the link between brain and gut health.
For example, gluten intolerance is frequently a feature of autism, and many autistic children will improve when
following a strict gluten-free diet. Many autistic children also tend to improve when given probiotics, either
in the form of fermented foods or probiotic supplements.
Dr. Andrew Wakefield is just one of many who have
investigated the connection between developmental disorders and bowel disease. He has published about 130-140
peer-reviewed papers looking at the mechanism and cause of inflammatory bowel disease, and has extensively
investigated the brain-bowel connection in the context of children with developmental disorders such as autism.
A large number of replication studies have also been
performed around the world, by other researchers, confirming the curious link between brain disorders such as
autism and gastrointestinal dysfunction.
Other Health Benefits of
Your body contains about 100 trillion bacteria -- more than
10 TIMES the number of cells you have in your entire body. Ideally, the ratio between the bacteria in your gut
is 85 percent "good" and 15 percent "bad."
In addition to the psychological implications discussed
above, a healthy ratio of good to bad gut bacteria is essential for:
Protection against over-growth of other microorganisms that could cause
Digestion of food and absorption of nutrients
Digesting and absorbing certain carbohydrates
Producing vitamins, absorbing minerals and eliminating toxins
Signs of having an excess of unhealthy bacteria in your gut
include gas and bloating, fatigue, sugar cravings, nausea, headaches, constipation or diarrhoea.
What Interferes With Healthy Gut
Your gut bacteria do not live in a bubble; rather, they are
an active and integrated part of your body, and as such are vulnerable to your lifestyle. If you eat a lot of
processed foods, for instance, your gut bacteria are going to be compromised because processed foods in general
will destroy healthy micro flora and feed bad bacteria and yeast.
Your gut bacteria are also very sensitive
Because of these latter items, to which virtually all of us
are exposed at least occasionally, it's generally a good idea to "reseed" the good bacteria in your gut by
taking a high-quality probiotic supplement or eating fermented foods.
Tips for Optimizing Your Gut
Getting back to the issue of inflammation for a moment,
it's important to realize that an estimated 80 percent of your immune system is actually located in your gut,
which is why you need to regularly reseed your gut with good bacteria.
Additionally, when you consider that your gut is your
second brain AND the seat of your immune system, it becomes easy to see how your gut health can impact your
brain function, psyche, and behaviour, as they are interconnected and interdependent in a number of different
ways—several of which are discussed above.
In light of this, here are my recommendations for
optimizing your gut bacteria.
Fermented foods are still
the best route to optimal digestive health, as long as you eat the traditionally made, unpasteurized versions.
Healthy choices include lassi (an Indian yoghurt drink, traditionally enjoyed before dinner), fermented milk
such as kefir, various pickled fermentations of cabbage, turnips, eggplant, cucumbers, onions, squash and
carrots, and fermented soy called natto.
If you regularly eat fermented foods such as these that, again, have not been pasteurized (pasteurization kills the
naturally occurring probiotics), your healthy gut bacteria will thrive.
Probiotic supplement. I am a
proponent of taking supplements that come from food (as I believe we aren’t getting the nutrients we need from
food we have access to today), and probiotics are definitely a needed supplement. If you do not eat fermented
foods, taking a high quality probiotic supplement is definitely recommended.
Probiotic Fibre Drink Mix
This is a scientifically
formulated probiotic blend, that provides 2 active strains of
bacteria, Lactobacillis acidophilus and Bifodobacterium lactis, both widely studied for their role in helping to
restore intestinal flora balance, with 4.5 billion bacteria in each 5 gram (1 teaspoon) serve. Fuel Factor
Probiotic fibre drink Mix contains prebiotics, which help feed probiotics and colostrum, lactoferrin, zinc and
l-glutamine for further gastrointestinal support. Because of It’s shelf stability as a powder, no refrigeration
VS 240050 for a 10 day supply or
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