How Gut Bacteria Affects Your Brain

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The bacteria, fungi, viruses and other microorganisms comprising your body’s microflora outnumber your body’s cells 10 to 1. It’s becoming increasingly clear that these tiny organisms play a MAJOR role in your physical and mental health.

Researchers in a UCLA proof-of-concept study confirmed the impact microflora has on brain function when probiotics (beneficial bacteria) altered participants’ brain function.

As reported by UCLA:

… 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 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, as opposed to trusting a “miracle drug” to do the work for you…

See: 7 Mood-Improving Foods

Another study published in the Dec. 2011 Journal of Neurogastroenterology and Motility reported that probiotic (good) bacteria known as Bifidobacterium longum NCC3001 helped normalized anxiety-like behavior in mice with infectious colitis. Separate research found the probiotic Lactobacillus rhamnosus had a marked effect on GABA (nervous system neurotransmitters) levels in certain brain regions, and lowered the stress-induced hormone corticosterone, resulting in reduced anxiety- and depression-related behavior.

Like brain neurons, you also have neurons in your gut, including serotonin-producing neurotransmitters. The greatest serotonin concentration, involving mood control, depression and aggression, is found in your intestines, not your brain – one reason why antidepressants, which raise serotonin levels in your brain, often don’t help depression, while proper dietary changes often do.

Your Gut Microbes Can Affect Your Health

Gut microbes are more crucial your health than previously thought. They impact:

  • Immune system function: Biologist Sarkis Mazmanian believes bacteria can train your immune system to distinguish between “foreign” microbes and those originating in your body.
  • Gene expression: Researchers using gene profiling found that the absence of gut bacteria during infancy permanently altered genes and signaling pathways involved in learning, memory, and motor control. Probiotics also help hundreds of your genes to express in a positive, disease-fighting manner.
  • Diabetes: Diabetics and non-diabetics have different gut bacteria populations, according to a Danish study.  Researchers concluded that type 2 diabetes in humans is “associated with compositional changes in intestinal microbiota.”
  • Obesity: One of the strongest areas of probiotic research to date is that the make-up of gut bacteria tends to differ in lean vs. obese people. Fact: Restoring your gut flora is an  important consideration influencing weight loss. (Read similar studies here.)

Your Gut Flora Is Constantly Under Attack

If you eat a lot of sugar, refined grains and genetically engineered foods (i.e. processed foods and beverages containing high fructose corn syrup and/or soy, both primary GE crops in the U.S.), your gut bacteria may be compromised. Processed foods destroy healthy microflora and feed bad bacteria and yeast. Your gut bacteria also can be harmed by:

  • Antibiotics, unless absolutely necessary (just make sure to reseed your gut with fermented foods and/or a probiotic supplement)
  • Conventionally-raised meats and other animal products; CAFO animals fed low-dose antibiotics; and genetically engineered grains
  • Processed foods (excessive sugars and “dead” nutrients)
  • Chlorinated and/or fluoridated water
  • Antibacterial soap
  • Agricultural chemicals

Since about 80 percent of your immune system is in your gut, reseeding it with healthy bacteria is important to prevent virtually ALL diseases, from colds to cancer, asthma, allergies, obesity, diabetes, autoimmune diseases, the aforementioned brain, behavioral and emotional problems – even neurological diseases. I recommend:

  • Avoiding processed, refined foods in your diet
  • Eating traditionally fermented, unpasteurized foods, which are excellent chelators of heavy metals and pesticides and help reduce your toxic load.  Healthy choices include:

1.  Fermented vegetables

2.  Lassi (apre-dinner Indian yoghurt drink)

3.  Fermented milk

4.  Natto (fermented soy)

Fermented vegetables are a great source of Vitamin K2 (a vital co-nutrient to both Vitamin D and calcium) if you ferment your own using the proper starter culture. Two or three ounces of fermented organic vegetables made with our specific starter culture contain not only 10 trillion beneficial bacteria, but 500 mcg of Vitamin K2.

Take a high-quality probiotic supplement. Most of your nutrients should come from food, but probiotics pose an exception if you don’t regularly eat fermented foods.

Bottom line: Nourishing your gut flora is extremely important, from cradle to grave.


Maria Virokhovsky

Thank you, very helpful article!

Thomas Grant
Thomas Grant2 years ago

Great article!

Shalvah Landy
Past Member 4 years ago

Very interesting thank you!

PrimaSICK B.
PrimaAWAY B4 years ago

Interesting Information. Actually ,most of this I have heard and read about due to my own health issues.
I appreciate the post but make sure you research more into it.
There are always more and some different points of opinions.

Natasha Salgado
Past Member 4 years ago

Thank you 4 the info!

Val M.
Val M4 years ago


Elena T.
Elena Poensgen4 years ago

Thank you :)

Virginia Belder
Virginia Belder4 years ago

Great article....

Bryan S.
Bryan S4 years ago

I haven't done it myself but it seems pretty easy to ferment vegetables. There's a guy on youtube (and wrote a book), "Sandor Katz", who goes through the steps.

Christine Stewart
Christine S4 years ago

Good information!