The bacteria, fungi, viruses and other microorganisms that comprise
your body’s microflora actually outnumber your body’s cells 10 to 1, and
it’s now becoming increasingly clear that these tiny organisms play a
MAJOR role in your health—both physical and mental.
The impact of your
microflora on
your brain function has again been confirmed by UCLA researchers who,
in a proof-of-concept study, found that probiotics (beneficial bacteria)
indeed altered the brain function in the participants.
As reported by UCLA:
“Researchers have known that the brain sends signals
to your gut, which is why stress and other emotions can contribute to
gastrointestinal symptoms. This study shows what has been suspected but
until now had been proved only in animal studies: that signals travel
the opposite way as well.
‘Time and time again, we hear from patients that they never felt
depressed or anxious until they started experiencing problems with their
gut,’ [Dr. Kirsten]Tillisch said. ‘Our study shows that the gut–brain connection is a two-way street.’”
The study, published in the peer-reviewed journal
Gastroenterology, claims
the discovery “carries significant implications for future research
that could point the way toward dietary or drug interventions to improve
brain function.” Naturally, I urge you to embrace dietary changes here,
opposed to waiting for some “miracle drug” to do the work for you…
Yes, Your Diet Affects Your Brain Function
The study enlisted 36 women between the ages of 18 and 55 who were divided into three groups:
- The treatment group ate yogurt containing several probiotics thought
to have a beneficial impact on intestinal health, twice a day for one
month
- Another group ate a “sham” product that looked and tasted like the yogurt but contained no probiotics
- Control group ate no product at all
Before and after the four-week study, participants’ underwent
functional magnetic resonance imaging (fMRI) scans, both while in a
state of rest, and in response to an “emotion-recognition task.” For the
latter, the women were shown a series of pictures of people with angry
or frightened faces, which they had to match to other faces showing the
same emotions.
“This task, designed to measure the engagement of
affective and cognitive brain regions in response to a visual stimulus,
was chosen because previous research in animals had linked changes in
gut flora to changes in affective behaviors,” UCLA explains.
Interestingly, compared to the controls, the women who consumed
probiotic yogurt had decreased activity in two brain regions that
control central processing of emotion and sensation:
- The insular cortex (insula), which plays a role in functions
typically linked to emotion (including perception, motor control,
self-awareness, cognitive functioning, and interpersonal experience) and
the regulation of your body’s homeostasis, and
- The somatosensory cortex, which plays a role in your body’s ability to interpret a wide variety of sensations
During the resting brain scan, the treatment group also showed
greater connectivity between a region known as the “periaqueductal grey”
and areas of the prefrontal cortex associated with cognition. In
contrast, the control group showed greater connectivity of the
periaqueductal grey to emotion- and sensation-related regions. According
to UCLA:
“’The researchers were surprised to find that the
brain effects could be seen in many areas, including those involved in
sensory processing and not merely those associated with emotion,’
Tillisch said…
‘There are studies showing that what we eat can alter the
composition and products of the gut flora — in particular, that people
with high-vegetable, fiber-based diets have a different composition of
their microbiota, or gut environment, than people who eat the more
typical Western diet that is high in fat and carbohydrates,’ [senior
author Dr. Emeran] Mayer said. ‘Now we know that this has an effect not
only on the metabolism but also affects brain function.’”
What is really remarkable to me is that this study showed any
improvement at all, since they used commercial yogurt preparations that
are notoriously unhealthy foods loaded with
artificial sweeteners,
colors, flavorings, and sugar. Most importantly the vast majority have
virtually clinically insignificant levels of beneficial bacteria.
Clearly, you would be far better off making your own yogurt from
raw milk.
Your Gut May Hold the Key to Better Brain Health
You may not be aware that you actually have two nervous systems:
- Central nervous system, composed of your brain and spinal cord
- Enteric nervous system, which is the intrinsic nervous system of your gastrointestinal tract
Both are created from identical tissue during fetal 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. It is now well established that the vagus nerve is
the primary route your gut bacteria use to transmit information to your
brain.
While many think of their brain as the organ in charge, your gut
actually sends far more information to your brain than your brain sends
to your gut… To put this into more concrete terms, you’ve probably
experienced the visceral sensation of butterflies in your stomach when
you’re nervous, or had an upset stomach when you were very angry or
stressed. The flip side is also true, in that problems in your gut can
directly impact your mental health, leading to issues like anxiety and
depression.
For instance, in December 2011, the
Journal of Neurogastroenterology and Motility reported
the novel finding that the probiotic (good bacteria) known as
Bifidobacterium longum NCC3001 has been shown to help normalize
anxiety-like behavior in mice with infectious colitis. Separate
research also found the probiotic Lactobacillus rhamnosus had a marked
effect on GABA (an inhibitory neurotransmitter that is significantly
involved in regulating many physiological and psychological processes)
levels in certain brain regions and lowered the stress-induced hormone
corticosterone, resulting in reduced anxiety- and depression-related
behavior.
Just as you have neurons in your brain, you also have neurons in your
gut — including neurons that produce neurotransmitters like serotonin,
which is also found in your brain. In fact, the greatest concentration
of serotonin, which is involved in mood control, depression and
aggression, is found in your
intestines, not your brain. It’s quite possible that this might be one reason why
antidepressants, which raise serotonin levels in your
brain, are often ineffective in treating depression, whereas proper dietary changes often help…
Your Gut Microbes Can Affect Your Health in Numerous Ways
In recent years, it’s become increasingly clear that the microbes in
your gut play a much more vital role in your health than previously
thought possible. In fact, probiotics, along with a host of other gut
microorganisms, are so crucial to your health that researchers have
compared them to “a newly recognized organ.” Besides research
implicating gut bacteria in mental health and behavior, other research
has shown that your microbiota also has an impact on:
- Immune system function: Biologist Sarkis
Mazmanian believes bacteria can train your immune system to distinguish
between “foreign” microbes and those originating in your body. His work
is laying the groundwork for new therapies using probiotics to treat a
variety of diseases, particularly autoimmune diseases such as multiple
sclerosis and Alzheimer’s. Mazmanian and colleagues were recently
awarded the MacArthur Foundation “genius grant” for identifying an
organism that originates in the human body (opposed to a fermented food)
that has demonstrable health benefits in both animal and human cells.
The organism has been named Bacteroides fragillis, and is found
in 15-20 percent of humans. His group hopes to one day be able to test
this body-originated bacteria in human clinical trials.
- Gene expression: Researchers have discovered that
the absence or presence of gut microorganisms during infancy permanently
alters gene expression. Through gene profiling, they were able to
discern that absence of gut bacteria altered genes and signaling
pathways involved in learning, memory, and motor control. This suggests
that gut bacteria are closely tied to early brain development and
subsequent behavior. These behavioral 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 behavior. 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.
- Diabetes: Bacterial populations in the gut of
diabetics differ from non-diabetics, according to a study from Denmark.
In particular, diabetics had fewer Firmicutes and more plentiful amounts
of Bacteroidetes and Proteobacteria, compared to non-diabetics. The
study also found a positive correlation for the ratios of Bacteroidetes
to Firmicutes and reduced glucose tolerance. The researchers concluded: “The
results of this study indicate that type 2 diabetes in humans is
associated with compositional changes in intestinal microbiota.”
- Obesity: The make-up of gut bacteria tends
to differ in lean vs. obese people. This is one of the strongest areas
of probiotic research to date, and you can read about a handful of such
studies here. The bottom line is that restoring your gut flora should be an important consideration if you’re struggling to lose weight.
- Autism: Establishment of normal gut flora in the
first 20 days or so of life plays a crucial role in appropriate
maturation of your baby’s immune system. Hence, babies who develop
abnormal gut flora are left with compromised immune systems and are
particularly at risk for developing such disorders as ADHD, learning
disabilities and autism, particularly if they are vaccinated before restoring balance to their gut flora.
To get a solid understanding of just how this connection works, I highly recommend reviewing the information shared by
Dr. Natasha Campbell-McBride in this previous interview.
Total Video Length: 1:13:21
Download Interview Transcript
Your Gut Flora Is Constantly Under Attack
Your gut bacteria are vulnerable to your diet and lifestyle. If you
eat a lot of sugar, refined grains, and genetically engineered foods
(i.e. processed foods and beverages of all kinds, as they are typically
loaded with high fructose corn syrup and/or soy, both of which are
primary GE crops in the US), your gut bacteria are going to be
compromised because processed foods in general will destroy healthy
microflora and feed bad bacteria and yeast. Your gut bacteria are also
very sensitive to and can be harmed by:
- Antibiotics, unless absolutely necessary (and when you do, make sure
to reseed your gut with fermented foods and/or a probiotic supplement)
- Conventionally-raised meats and other animal products, as CAFO animals are routinely fed low-dose antibiotics, plus genetically engineered grains, which have also been implicated in the destruction of gut flora
- Processed foods (as the excessive sugars, along with otherwise “dead” nutrients, feed pathogenic bacteria)
- Chlorinated and/or fluoridated water
- Antibacterial soap
- Agricultural chemicals
How to Optimize Your Gut Flora
Considering the fact that an estimated 80 percent of your immune
system is located in your gut, reseeding your gut with healthy bacteria
is important for the prevention of virtually ALL diseases, from colds
to
cancer. To do so, I recommend the following strategies:
1. Avoid processed, refined foods in your diet.
2. Eat traditionally fermented, unpasteurized foods: Fermented foods are
the best route to optimal digestive health, as long as you eat the
traditionally made, unpasteurized versions. Some of the beneficial
bacteria found in fermented foods are also excellent
chelators of heavy metals and pesticides, which will also have a beneficial health effect by reducing your toxic load. Healthy choices include:
- Fermented vegetables
- Lassi (an Indian yoghurt drink, traditionally enjoyed before dinner)
- Fermented milk, such as kefir
- Natto (fermented soy)
Ideally, you want to eat a variety of fermented foods to maximize the
variety of bacteria you’re consuming. Fermented vegetables, which are
one of my new passions, are an excellent way to supply beneficial
bacteria back into our gut. And, unlike some other fermented foods, they
tend to be palatable, if not downright delicious, to most people.
As an added bonus, they can also be a great source of
vitamin K2 if
you ferment your own using the proper starter culture. We tested
samples of high-quality fermented organic vegetables made with our
specific starter culture, and a typical serving (about two to three
ounces) contained not only
10 trillion beneficial bacteria, it
also had 500 mcg of vitamin K2, which we now know is a vital co-nutrient
to both vitamin D and calcium. Most high-quality probiotic supplements
will only supply you with a fraction of the beneficial bacteria found in
such homemade fermented veggies, so it’s your most economical route to
optimal gut health as well.
3. Take a high-quality probiotic supplement.
Although I’m not a major proponent of taking many supplements (as I
believe the majority of your nutrients need to come from food),
probiotics is an exception if you don’t eat fermented foods on a regular
basis.
Nurturing Your Gut Flora Is One of the Foundations of Optimal Health
Mounting research indicates the bacterial colonies residing in your
gut may play key roles in the development of cancer, asthma, allergies,
obesity, diabetes, autoimmune diseases and even brain, behavioral and
emotional problems like ADHD, autism and depression. 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 behavior 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 nourishment. Eating
fermented foods should be your primary strategy, but if you don’t enjoy
the taste of fermented foods, taking a probiotic supplement is
definitely advised. I recommend looking for a probiotic supplement that
fulfills the following criteria, to ensure quality and efficacy:
- The bacteria strains in the product must be able to survive your
stomach acid and bile, so that they reach your intestines alive in
adequate numbers
- The bacteria strains must have health-promoting features
- The probiotic activity must be guaranteed throughout the entire production process, storage period and shelf life of the product