The Impact Of A Healthy Gut vs An Unhealthy Gut

Have you ever experienced symptoms such as bloating, indigestion or flatulence after eating? If so, you’re not alone.

These so-called ‘common’ digestive symptoms could actually be a sign that your gut health is compromised.

An estimated 86% of adults have suffered from some form of gastrointestinal problem (1), while between 60 and 70 million are affected by digestive disease (2). In 2017, the World Health Organisation found that we spend an estimated $10 billion dollars per year on antacid medications; a number which is set to double by 2050. Furthermore, the prevalence of gastroesophageal reflux disease or GERD is on the rise, with levels currently at 40% of the general population (3).

However, these digestive conditions are not the only issue. There is a growing population of individuals with compromised gut health who may not even realize it. Common conditions such as chronic fatigue, mood disorders, allergies, skin conditions, autoimmune diseases and arthritis are being increasingly linked to poor gut health (4,5). In fact, people who regularly experience functional bowel problems such as constipation, bloating and diarrhea have a greater chance of developing mood disorders such as anxiety and depression (6). For years it was believed that anxiety and depression might contribute to symptoms of an irritable bowel however it turns out that it’s the opposite – gut dysfunction actually contributes to mood disorders (7). This connection is believed to be driven by the enteric nervous system, which resides in the gut yet intimately communicates with the brain (8).

As you can see, optimal gut functioning is not just important for our digestive health, but for the health of our entire body system.

“All disease begins in the gut” –Hippocrates

The good news is that it is entirely achievable to restore and maintain optimal gut health, you just need to know what to look for…

What exactly constitutes the gut?

The gastrointestinal tract or ‘gut’ comprises the central organ system which accommodates the processing, digestion, absorption and elimination of food within the body. It is the primary way for the body to create and receive energy and nutrients while sitting as a fundamental element of overall health and survival.

What is a healthy gut?

A healthy gut is one that is functioning in a way to support optimal digestion, absorption and assimilation of food and nutrients while also preventing unwanted microbes, allergens and toxins from entering the body. When these factors are not being closely monitored, it can throw the whole body into a state of havoc; leaving it open to disorder and disease.

Let’s take a closer look…

The Key Requirements For Optimal Gut Functioning

Efficient Breakdown & Metabolism Of Food

The gut is solely responsible for the digestion, absorption and assimilation of food. Once food is chewed and swallowed, it is sent straight to the stomach where the environment is highly acidic. The primary reason for this is to kill any unwanted substances such as microbes and toxins before they can reach the next phase of digestion. The acidity is also required to break down heavier foods, especially proteins so that they can be absorbed later in the small intestine. As the food is released into the small intestine, it is first met with bile from the liver which primarily functions to break down fats. At this stage, the pancreas releases certain enzymes which raise the pH level for safe passage through the small intestine. It is here in the small intestine where food travels slowly, allowing passage of nutrients through the thin cellular walls and into the bloodstream along the way. Once everything required has been absorbed, any remaining fibers, toxins and wastes are taken through the colon for safe elimination from the body.

Gut Tract
Source: google images/free license.

Bacteria & Nutrients

A healthy gut is responsible for maintaining over 3 pounds of live bacteria at any given time; consisting of anywhere between 500-1000 various bacterial species. It is these millions of bacteria lining our gut which produce short-chain fatty acids from feeding off of the fibers in our diet. These acids are a key energy source within the body, especially for the brain. In fact, low levels of these acids within the gut have been associated with greater feelings of anxiety and depression (9). These bacterial colonies within the gut also play a key role in synthesizing certain vital nutrients such as B12, K2, folic acid and biotin (10) which are required for a myriad of critical bodily functions.


Did you know that our level of immunity is largely controlled by our gut? Between 70-80% of our immune health is influenced by the gut as key players in immune functioning such as B and T cells line the gut waiting to attack at the first sign of invasion. When the gut is not functioning optimally our immune processes can become compromised.

Maintaining Blood Sugar Balance

You’ve probably heard the importance of maintaining a healthy blood sugar balance, but did you know that your gut bacteria may be the real dictators of blood sugar balance? High blood glucose can lead to insulin resistance and even diabetes if left unaddressed. While we know that following a low GI diet can go a long way to support this, studies suggest that our bacterial composition may also play a role. In fact, several studies have identified altered microbial composition as a contributing factor to disorders such as obesity through their contribution to insulin resistance and systemic inflammation (11).


Have you heard the expression ‘I had a gut feeling?’ Well, it turns out that there may be more truth to this phrase than previously believed. Our gut and brain communicate via a pathway known as the ‘vagal nerve’ which allows for direct communication and transportation of neurotransmitters between the brain and the gut. In fact, 90% of the well know happy hormone ‘serotonin’ is produced in the gut.

Genetic Expression

That age-old belief that you are defined by your genes has finally been debunked – it turns out that our health is more greatly influenced by the environment which we create for our genes. In other words, you may be stuck with your given set of genes but, whether or not these genes are actually expressed is a whole different - and much more important - story.

Unhealthy lifestyle choices such as poor diet, chronic stress and lack of sleep have shown the ability to turn on undesirable genes, such as those associated with aging and disease, while healthy lifestyle choices such as exercise and a balanced gut bacteria can switch these genes off! Research is still ongoing in this area, however, scientists believe that the gut may play a central role in determining genetic expression (12).

What does poor gut health look like?

One of the easiest ways to identify a ‘gut in trouble’ is the experience of any of the symptoms or disorders discussed above. Mood issues, digestive problems, inflammation, imbalanced blood sugar and nutrient deficiencies may all be signs that your gut needs a little extra TLC. That being said, there are a number of key behaviors, which have become the norm in modern-day society, but have actually been identified as detrimental to our gut health:

Medication Overload

Let’s face it, we’ve become a ‘pill-popping’ society and our bodies are beginning to rebel. Overuse of medications such as anti-inflammatories, antibiotics, steroids and acid blockers can disrupt and prevent normal digestive functioning (13).

Poor Diet

It’s common knowledge that eating highly processed, sugar dense and nutrient-poor food poses harmful influences on health. This harm is largely due to the impact of poor diet on the gut. These foods can lead to pathological, yeast and bacterial overgrowth, while the low fiber content of processed, high-sugar diets essentially starve the healthy gut bacteria by completely eliminating their main food source.


Stress is a plague in modern society that is slowly running humans into a state of poor health. When stress is detected, the sympathetic nervous system is automatically switched on, regardless of whether a physical, emotional or biochemical stressor is perceived. When the sympathetic nervous system becomes dominant it switches on the ‘fight or flight’ mode, which automatically turns down any process which is not deemed to be vital during a survival state - including rest and digestion. Over time, a digestive system that is forced to operate within a sympathetic state can alter the normal gut bacterial constitution and lead to conditions in which the health of the gut lining becomes compromised, such as having a leaky gut which cannot appropriately differentiate between the uptake of nutrients and toxic substances (14).


A subpar digestive system is a breeding ground for infection; particularly a chronic low-grade infection such as yeast overgrowth, parasites or small intestinal bacterial overgrowth. In fact, research has shown that individuals with compromised gut health have demonstrated greater levels of low-grade inflammation, resulting in impaired mucosal integrity within the duodenum; the first part of the small intestine (15).

Increased Toxic Exposure

As mentioned above, a healthy gut works to minimize exposure to high-level toxins through the acidic stomach environment. Additionally, as the gut acts as a semipermeable barrier to let in nutrients and keep out toxins and pathogens, the integrity of the gut barrier is critical for appropriately controlling toxic exposures.

If the health of your gut becomes compromised, gut bacteria can easily become exposed to toxins such as mercury and mold which have been linked to endocrine and neuronal disruption as well as respiratory disorders such as asthma (16,17).

So, What Can You Do To Improve Your Gut Health?

It is absolutely achievable to regain your gut health through proper testing, dietary and lifestyle adjustments. In fact, with the right routine, we can reverse years of intestinal damage through unhealthy diets and behaviors. The key is to identify the root cause of your imbalance by figuring out what is going on in your body and determining what could be affecting your body’s ability to absorb and digest nutrients correctly.

Check out our article 'how to create and maintain a healthy gut', which explains everything you need to know about keeping your gut functioning for optimal health, including the complete functional medicine gut healing protocol.

Comment below and let us know if you’ve ever experienced some of the above symptoms, and how gut health has played a role in your life!

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1. Press review copies of Mintel’s Gastrointestinal Remedies UK 2016 report and interviews with Senior Consumer Lifestyles Analyst Jack Duckett are available on request from the press office.

2. National Institutes of Health, U.S. Department of Health and Human Services. Opportunities and Challenges in Digestive Diseases Research: Recommendations of the National Commission on Digestive Diseases. Bethesda, MD: National Institutes of Health; 2009. NIH Publication 08–6514.

3. Cohen E, Bolus R, Khanna D, Hays RD, Chang L, Melmed GY, et al. GERD symptoms in the general population: prevalence and severity versus care-seeking patients. Dig Dis Sci [Internet]. NIH Public Access; 2014 Oct [cited 2018 May 27];59(10):2488–96. Available from:

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