Surprising Ways Your Digestive Health Affects Your Brain


By  Deane Alban

Contributing Writer for  Wake Up World

Your brain and your stomach are integrally entwined. Every time you get butterflies in your stomach or feel gut-wrenching distress, your brain is affecting your stomach. What goes on in your stomach affects your brain as well.

We’re going to delve into one specific area of intestinal health that has a surprising influence on your brain — your intestinal flora.

Amazing Friendly Flora Facts

Your digestive tract is not an inert pipe through which food passes — not by a long shot! Your intestines house over 100 trillion bacteria of around 500 different species.

These bacteria are referred to collectively as your intestinal flora. There are more microorganisms in your digestive tract than there are cells in your body! Amazingly, the number of bacteria in your gut outnumbers that of your own cells by ten to one.

When we’re born, our digestive tracts are sterile, but during the first two years of life different strains of bacteria take hold. By this time, your flora is more or less set unless you move to another country or drastically change your diet.

Each person has their own mix of intestinal bacteria, similar to having a unique fingerprint.

These beneficial microorganisms are essential for your health. They are needed in digestion to break down and absorb food.

They keep harmful bacteria in check and help keep your immune system healthy. They help you absorb calcium, zinc, and magnesium, and can even manufacture vitamins you need such as vitamin K and the essential B complex.

If you’ve ever experienced digestive upset after taking antibiotics, you’ll really appreciate what good bacteria do for you. Antibiotics kill both the good bacteria along with the bad.

When the proper balance between them is disrupted, you have entered a state called dysbiosis. This can cause nausea, diarrhea, and abdominal cramps, or overgrowth leading to yeast infections.

This is why it’s a good idea to take a probiotic supplement along with your antibiotic.

Friendly Flora Foes

Since digestive bacteria balance is so important, how does it get so messed up? Some things that destroy beneficial bacteria besides antibiotics include:

  • Chlorine and fluoride in water
  • Some artificial sweeteners
  • Antibacterial soap
  • Protein deficiency
  • Overacidity
  • Stress
  • Heavy metal exposure
  • Consumed from  meat and dairy  (unless it’s specifically raised antibiotic-free)
  • Poor diet

Bacteria Balance and Your Brain

You’ll never get rid of all the bad bacteria, nor is it necessary. You only need to strive for balance between the good guys and the bad guys for optimal health.

The Good Guys

Lactobacilli and Bifidobacteria are two of the most prevalent bacteria in your gut and are the mainstays in most probiotic supplements. They act as antioxidants, protecting your brain from free radical damage.

These good bacteria lower immune system compounds called cytokines.  Cytokines are chemical messengers that regulate the intensity of your immune response and lead to chronic inflammation. Cytokines are seen at elevated levels in patients with mood disorders, depression, anxiety, and cognitive disorders.

The Bad Guys

An overabundance of bad bacteria leaves toxic byproducts called lipopolysaccharides. Lipopolysaccharides have numerous negative affects on your brain:

  • Lower dopamine and serotonin levels
  • Damage to the hippocampus, the seat of the memory
  • Increased levels of the stress hormone cortisol
  • Increased inflammation
  • Increased oxidative damage

Here’s a highly informative video by Dr. Bryan Walsh explaining more ways that lipopolysaccharides damage your health. You’ll likely be surprised at how many problems can be caused by microorganism imbalance in the digestive tract.

Achieving Balance

You can replenish your good bacteria by avoiding the risk factors listed above and by adding fermented foods to your diet. Most traditional cultures wisely include some fermented foods. Add these to your diet to boost your friendly flora naturally:

  • Traditional pickled vegetables of all kinds. This includes sauerkraut and kimchi. They must be unpasteurized as heat destroys good bacteria.
  • Fermented dairy products such as yogurt and kefir.
  • Fermented soy foods like miso and tamari — cheap soy sauce won’t contain any live bacteria.
  • Cacao beans are fermented, making high quality dark chocolate a reasonable source of good bacteria.

If you can’t eat enough of these foods to make a difference in your digestive health, consider taking a good probiotic supplement. Look for one that contains lactobacilli and/or bifidobacteria with 10 billion to 20 billion active CPD (Cultures Per Dose). The more strains of bacteria included, the better.

Previous articles by Deane:

About the author:

deane alban

Deane Alban holds a bachelor’s degree in biology and has taught and written on a wide variety of natural health topics for over 20 years. Her current focus is helping people overcome brain fog, “senior moments”, and other signs of mental decline now, and preventing Alzheimer’s and dementia in the future.

The human brain is designed to last a lifetime, but modern life takes a greater toll on the brain than most people realize. Deane teaches the best ways to keep your brain healthy and stay mentally sharp for life at her website


If you've ever found value in our articles, we'd greatly appreciate your support by purchasing Mindful Meditation Techniques for Kids - A Practical Guide for Adults to Empower Kids with the Gift of Inner Peace and Resilience for Life.

In the spirit of mindfulness, we encourage you to choose the paperback version. Delve into its pages away from screen glare and notifications, allowing yourself to fully immerse in the transformative practices within. The physical book enriches the learning process and serves as a tangible commitment to mindfulness, easily shared among family and friends.

Over the past few years, Wake Up World has faced significant online censorship, impacting our financial ability to stay online. Instead of soliciting donations, we're exploring win-win solutions with our readers to remain financially viable. Moving into book publishing, we hope to secure ongoing funds to continue our mission. With over 8,500 articles published in the past 13 years, we are committed to keeping our content free and accessible to everyone, without resorting to a paywall.