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The Effects of Bad Gut Bacteria On The Body and What You Can Do About Them

Updated on June 20, 2022
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The Effects of Bad Gut Bacteria On The Body and What You Can Do About Them
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You may not know it yet, but there are bacteria in your gut. They exist in a symbiotic relationship with your body, calling your body their home.  

In a typical human gut environment, there is a balance of good and bad bacteria. Once this balance is disrupted, health problems begin to occur. 

The Effects of Bad Gut Bacteria On The Body and What You Can Do About Them 1

Why is there Bacteria in the Gut?

Bacteria make up 90% of microorganisms found inside the human gut. They are introduced into the human body from birth to adulthood. 

There is a negative perception surrounding bacteria. People view them as bad because they cause diseases.

The Effects of Bad Gut Bacteria On The Body and What You Can Do About Them 2

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While it’s true that there are harmful ones, there are also good bacteria in your gut. There are harmless microbes that help you stay healthy.

The bacteria in your gut help maintain good health by doing the following:

  • They aid in digestion
  • They break down toxins
  • They supply the gastrointestinal tract with energy
  • They protect the gut
  • They produce vitamins
  • They ‘train’ the immune system

The intestinal microbiota affects human health. A healthy balance must be maintained at all times to achieve optimum health conditions.

What are the Effects of Bad Gut Bacteria on the Body?

The overwhelming presence of bad bacteria in the gut harms the various organ systems in the human body. A negative balance of bacteria in the gut directly affects our organs, bodies, and overall health. 

On the Heart

A particular type of bacteria produces a chemical that the liver converts into trimethylamine-N-oxide or TMAO. TMAO causes the build-up of cholesterol in blood vessels which may lead to heart disease.

On the Kidneys

Aside from causing heart problems, the production of TMAO is also associated with the development of chronic kidney disease. It can also lead to the development of kidney stones.

On the Liver

Having too much gut bacteria turns fiber into fatty acids. These fatty acids may be deposited into the liver, which may lead to the development of what is known as Metabolic Syndrome.

When left untreated, metabolic syndrome can lead to:

  • Obesity
  • Heart disease
  • Type 2 diabetes

On the Joints

Bad gut bacteria have been linked to joint problems like Rheumatoid Arthritis and Osteoarthritis. This is because gut microbiomes exert an influence on the immune system. Bad bacteria in the gut trigger inflammatory responses. 

On the Central Nervous System

The gut has many nerve endings that communicate directly with the brain. Doctors call it the “gut-brain axis.” Having too much bad gut bacteria has been linked to:

  • Autism
  • Anxiety
  • Depression

On the Digestive System

Poor gut health affects overall health. It sets the stage for the development of several conditions related to the digestive tract.

These conditions include:

  • Ulcerative Colitis
  • Crohn’s Disease
  • Celiac Disease
  • Colon Cancer
  • Irritable Bowel Syndrome

These conditions often present with accompanying weight loss and abdominal pain. 

On the Immune System

An unhealthy gut significantly affects the immune system by increasing systemic inflammation. This causes a cascade of inflammatory events that may lead to autoimmune diseases such as type 1 diabetes.

On Mental Health

Gut inflammation and dysbiosis in the intestinal flora are associated with poor mental health. This is because of the gut-brain axis. Anxiety and depression are just some of the mental health issues linked to poor gut health. 


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How Do You Know if You Have Bad Gut Bacteria?

Bacterial overgrowth causes an imbalance in the typical environment of the gut. When this happens, you’ll begin to notice tell-tale signs that you’d sometimes ignore, thinking they will pass.

The most common ones include:

  • Stomach disturbances like abdominal pain, bloating, gas, diarrhea, constipation, and heartburn
  • Constant fatigue
  • Persistent sleepiness
  • Poor concentration
  • skin issues
  • Weight problems (unintentional weight loss or gain)

More severe conditions related to having too much bad gut bacteria include Crohn’s disease and Irritable Bowel Syndrome.

At-home microbiome test kits provide a comprehensive picture of your gut microbiota. Thryve Gut Health Program:

  • Will give you information on bacterial species inside your gut
  • Has customized food and probiotic recommendations to help maintain gut health

How Do You Restore Good Gut Health?

Because an unhealthy gut may lead to health problems, it’s essential to restore it to good health. But how does one do that, exactly? 

A healthy gut is a product of several aspects coming into play - lifestyle, diet, and environmental factors.

Here are several ways to improve not just your gut health but also your overall health and wellness. 

Avoid unnecessary use of Antibiotics

Doctors prescribe antibiotics to treat bacterial infections. But as we all know, too much of anything is bad. Antibiotic overuse not only causes antibiotic resistance but may affect gut health, too. 

Research has shown that antibiotics can damage the gut microbiome. This is why it’s important to discuss options with your doctor before antibiotic use.


The food that we eat passes through the gastrointestinal tract, and they directly affect gut health.

To ensure a healthy gut, it’s important to have healthy eating habits. This means making the right dietary choices.

People who eat plenty of plant-based foods have shown a healthier gut microbiome. This is compared to those who eat meat. 

On the one hand, a high in sugar and sweets diet causes an imbalance between the good and bad bacteria in the gut. A high sugar, high fat diet negatively affects the gut microbiome.

Health experts recommend avoiding certain foods like red meat, fried food, artificial sugar, fructose-rich food, alcohol, processed foods, and caffeine. 


Regular exercise helps control weight, prevent obesity, improve blood flow, and positively impact heart health.

Research has shown that having consistent exercise habits improve gut health.

Get good quality sleep

When it comes to sleep, the number of hours is as important as quality. Getting 8 hours of restless sleep won’t do any good. 

In a study conducted on animals, researchers found out that disturbed sleep negatively impacts gut health. On the one hand, good quality sleep has been linked to improvements in human gut health, cognition, and mood.

Manage Stress

Did you ever notice how your digestive tract acts up when you’re feeling anxious? “Butterflies in the stomach” is often associated with stress, anxiety, and poor mental health.

Animal studies revealed that various stressors could negatively affect the balance of bacteria inside the gut and harm gut health. 

In humans, the stressors may come in the forms of psychological and environmental stress, deprivation of sleep, and the disruption of the body’s internal clock. 

Proper stress management is essential for a healthy immune system and good overall health.

Some stress management techniques include:

  • deep breathing exercises
  • meditation
  • progressive muscle relaxation

Prebiotics and Probiotics

To ensure gut health, it’s vital to maintain the balance of bacteria. We want the good ones to continue growing and the bad bacteria to stop multiplying. 

To do this, we feed the good bacteria in the gut with the food that they like - prebiotics. We add living microbes directly into the gastrointestinal tract through probiotics. Thus, prebiotics and probiotics are essential to good gut health. 

Probiotics come in the form of food and oral supplements. This gives you more options for your sources of probiotics.

What are the Best Foods for Gut Bacteria?

We are what we eat, they say - and this has been proven true with the knowledge that our gut health depends on what we feed the bacteria inside our gut microbiome. Certain foods are known to make the gut healthy.

Some of the most recommended foods to combat unhealthy gut and achieve a healthy gut are listed below. Dietary modification, no matter how small, will help you improve your gut health significantly.


Almonds contain 12.5 grams of fiber per 100 grams. They have high fiber content and possess prebiotic characteristics by promoting good bacterial growth while preventing bad bacteria.


Bananas provide the gut with a kind of fiber known as inulin. It promotes the growth of beneficial bacteria.


There are many kinds of cheese, but not all of them are excellent sources of probiotics. The good ones for the bacteria in your gut are:

  • Cottage
  • Cheddar
  • Mozzarella
  • Gouda cheese

Fermented foods 

Fermented foods are made with yeast and bacteria. Examples of fermented foods include:

  • Kefir
  • Kimchi
  • Kombucha
  • Miso
  • Natto
  • Pickles
  • Sauerkraut
  • Tempeh
  • Yogurt

These are considered natural sources of probiotics and are thus beneficial for gut health. 


Garlic is an herb known for its taste and prebiotic properties. It helps ensure a healthy gut by promoting the growth of good bacteria while preventing bad bacteria from taking space inside the digestive tract.

Green Leafy Vegetables

Green leafy vegetables contain a special kind of carbohydrates that supplies good bacteria with food. Plus, veggies are also high in fiber which helps with digestion.


Legumes have prebiotic properties that help restore an unhealthy gut to good health. Soybeans, baked beans, and red kidney beans are excellent examples. 


Polyphenols are compounds found in colorful food like green tea. They help maintain the balance of bacteria inside the gut as they fight off pathogenic bacteria and encourage the growth of good bacteria in your gut. 

Additionally, they are good at easing the symptoms of peptic ulcers and inflammatory bowel disease. 

The Effects of Bad Gut Bacteria On The Body and What You Can Do About Them 2

The Best Gut Health Test

Ombre’s Gut Health Test is an excellent choice for budget-conscious people who want value for their money.

Good Gut Health for Overall Health and Wellness

Your overall health and wellness depend on various systems working together efficiently. Each of our organs is dependent on one another - if one fails, a chain of reactions happens.

As difficult as it is to understand, intestinal bacteria do not simply affect the intestinal tract alone. 

More than bloating, gas, and chronic fatigue, patients are more prone to developing a slew of other diseases. These include:

  • Irritable bowel syndrome
  • Inflammatory bowel diseases (Crohn’s disease)
  • Type 1 diabetes
  • Heart disease
  • Many more

A healthy gut contributes to a healthy you. So pay attention to what you eat - and what you don’t eat. A few healthy changes will go a long way.


Best Gut Health Test

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Content Contributor
Joel is a writer that loves exploring DNA, at-home health, and optimizing my health. He believes that the democratization of home health is in its early stages.
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