It all begins in the gut: Bacteria’s role in overall health

“All disease begins in the gut.” – Hippocrates

Now, more than 2000 years later, researchers are finding that old Hippocrates was on to something. Up until recently, the medical community largely neglected the importance of gut health in relation to the rest of our body. However, with the emerging focus on the human microbiome and its role in disease, we are starting to realize how right Hippocrates was!

Our digestive tract is one long passageway through our body.  It is a barrier between the outside world and our insides. Our digestive tract contains specialized cells that regulate what stays in the passageway and what gets absorbed. They do this with the help of our friendly gut bacteria – tens of trillions of them!

In many ways, our gut bacteria are still as vast and mysterious as the Milky Way, but researchers are beginning to investigate this new frontier of medicine. What they are finding is that when we do not have enough of the good bacteria and too much bad bacteria, our other bodily systems are impacted.


Do you ever wonder how someone can live off French fries and not gain a pound? Well that largely has to do with their gut bacteria. The bacteria in the gut play a big role in regulating the rate of our metabolism. They are responsible for the extraction of calories and nutrients from food and the foods you crave.

Different species of bacteria will convert the same foods into different products.  This means that if you have a harmful balance of gut bacteria, they convert even healthy foods into compounds that increase fat storage and insulin resistance. Healthy gut bacteria convert our foods in to compounds that help burn fat.

Cardiovascular Health

Turns out it might not be red meat and eggs that are harming your heart. Rather, it is how the bacteria in your gut are interacting with the food. Trimethylamine N-oxide (TMAO) is a compound linked to clogged arteries, heart disease, and stroke. Bad gut bacteria such as Clostridia, Proteus, Shigella, and Aerobactercan convert lecithin in egg yolks and carnitine in red meat to TMAO thus increasing risk of heart attack and stroke.

Mental Health

We have all experienced “butterflies” in our stomach. We know that nervousness can often cause digestive troubles. The gut is definitely affected by the brain, but scientists our now finding that our brain is affected by our gut bacteria  even more.

The good bacteria in your gut produce hundreds of neurochemicals that the brain uses to regulate processing, learning, memory and mood. Gut bacteria produce about 90-95% percent of the body’s supply of serotonin. Some beneficial bacteria can influence GABA (a chemical that helps you feel calm) receptors in the brain.


Our intestines contain more immune cells than the rest of our body. The good bacteria dynamically interact with the intestinal wall where we have immune tissue. Our friendly bacteria send signals to activate our lymphocytes (killer cells) to keep the bad guys out of our body. In turn, these lymphocytes signal the production of a type of antibody (IgA) that helps protect our intestinal wall. Essentially, you cannot produce a healthy immune response without enough good bacteria.

Autoimmune disorders occur when we don’t have enough good bacteria and we have too much bad bacteria (also called dysbiosis). The bad bacteria produce chemicals that damage the lining of our digestive tract. At the same time, when we lack good bacteria, certain chemicals in our food do not get converted properly. This means these unconverted chemicals leak through the damaged gut cell walls and into the blood stream. Our immune cells then attack these chemicals causing more damage resulting in inflammation and all other sorts of problems.


Gut bacteria help by “locking down” floating estrogen. Together they are both eliminated when we poop (half your poop is bacteria btw).  This prevents estrogen from being reabsorbed in the body, which is good because too much estrogen in the body (estrogen dominance) is the cause of many female reproductive disorders.

Cortisol, also known as the “stress hormone,” is released to help the body in stressful situations. Most of us produce way too much cortisol, but our beneficial microbes can help keep cortisol levels in check. One study revealed that students preparing for a large exam who consumed a probiotic-rich beverage for eight weeks had lower levels of cortisol.


Food sensitivities are so rampant in modern times. Many people blame a particular food – gluten is evil, dairy is the devil! But it’s not the foods’ fault. When you have a sensitivity to certain foods, it actually means that you are missing the good bacteria to digest this food. Our genetics are sometimes a factor, but other stressors are at play as well.

Have a sensitivity? There is good news! Overtime, you can rebuild your gut flora and digest those much-loved foods that now make you bloated and feel crampy. I work with clients to help them balance their gut flora so they can go back to eating the foods they love.


Thriving health begins in the gut. The organs of your digestive system together with your gut flora, work with hormones, webs of nerves, and your blood to keep you healthy and balanced.

It’s important to know that without a balanced gut, your body can never get the nutrients it needs for optimal health. Fortunately, I can help you design your diet so you get everything you need to look and feel fantastic. Let’s do your gut some good!


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