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How to Starve Bad Gut Bacteria
Updated on August 13, 2023
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How to Starve Bad Gut Bacteria

Our gut health significantly impacts our overall well-being. It affects both our physical and mental health.1,2

The human digestive system is home to trillions of good and bad bacteria. These good and bad bacteria collectively make up the gut microbiome.3 

Starving bad gut bacteria is crucial for several reasons. It helps restore your gut microbiome and keep your immune system strong.4

The balance between these bacteria has an instrumental impact on our health. It’s influenced by genetics, lifestyle, diet, and more.5

What are Gut Bacteria and Why Are They Important?

How to Starve Bad Gut Bacteria 3
Intestinal villi with bacteria and viruses. Microscopic villi, capillaries for digestion and absorption of food. Human intestine. Concept of a healthy or diseased intestine. Loop

Gut bacteria belong to a group called gut microbiota or gut flora. This refers to the diverse community of microorganisms in our gastrointestinal tract. These microorganisms include:6

  • Bacteria
  • Viruses
  • Fungi
  • Other microbes

“These combinations of organisms help to maintain homeostasis—a balance that impacts every system in the body,” explains our in-house medical expert Dr. Rizza Mira.

The term "bacteria" may often have negative connotations. However, it's important to note that not all bacteria in our gut are harmful. In fact, there is a balance of good and bad bacteria in the gut.

Gut bacteria are beneficial and vital in maintaining our health. This is because of their involvement in several essential bodily functions.

”There are more and more studies that link gut bacteria to the prevention of diabetes, cancers, and brain pathologies,” says Dr. Mira.

For example, gut bacteria have the following roles:6

  • Supports immune system functions
  • Breaks down toxic food compounds
  • Synthesize vitamins and amino acids such as vitamin K and certain B vitamins

Furthermore, gut bacteria protect the body from harmful pathogens. These pathogens can enter through food or water.

Understanding Gut Microbiome: A Community Inside You

Bacteria in the gut microbiome are either good bacteria or bad bacteria.

Good Gut Bacteria

Good gut bacteria, or probiotics, are beneficial for our digestive health. They perform several functions, including:7

  • Vitamin synthesis
  • Digestion and absorption assistance
  • Infection prevention
  • Immunity stimulation

Bad Gut Bacteria

Bad bacteria also inhabit the gut. However, they do not harm the gastrointestinal tract because they’re balanced with good bacteria.

Bad bacteria can become pathogenic8 or opportunistic7 bacteria. This happens when they overgrow and disrupt the balance of the gut microbiome. 

The body is more prone to infection and complications when bad bacteria exceed good bacteria. 

Examples of health issues caused by bad gut bacteria include:7

  • Intestinal putrefaction
  • Production of bacterial toxins
  • Production of carcinogenic substances
  • Gas production.

When there are not enough good bacteria or an overgrowth of bad bacteria, this can lead to dysbiosis.9


Dysbiosis is a state of microbial imbalance. It’s associated with the following conditions:

  • Irritable bowel syndrome (IBS)
  • Inflammatory bowel disease (IBD)10
  • Mental health disorders2

“There is also increasing interest in the effects of dysbiosis in the pathology of diabetes mellitus, cancer, and obesity,” says Dr. Mira.

The interactions between the gut microbiome and the body are complex and multifaceted. Their core roles include:

  • Supporting the immune system
  • Synthesizing essential vitamins
  • Ensuring optimal digestion and absorption in the body

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What Impact Does an Unhealthy Gut Have on Your Health?

Maintaining a healthy gut is crucial for overall well-being. When something disrupts the balance of good and bad bacteria in the gut microbiome, it can lead to various health issues.

Symptoms of an Imbalanced Gut

An imbalanced gut can manifest through various symptoms that can vary from person to person. Some common signs of an unhealthy gut include:

  • Gut issues – Digestive problems are often associated with an imbalanced gut.11 Examples include bloating, gas, diarrhea, constipation, and IBS. These symptoms can arise from an overgrowth of bad bacteria or a lack of beneficial bacteria.
  • Food intolerances – An unhealthy gut can increase sensitivity to certain foods. The consequences include allergies or intolerances. This occurs when the gut lining becomes compromised. Undigested food particles and toxins can enter our system and trigger immune responses (i.e. leaky gut syndrome).12
  • Weight changes – Imbalances in the gut microbiome are sometimes linked to weight fluctuations. An unhealthy gut may contribute to obesity.10 This is because certain bacteria can affect metabolism and fat storage.
  • Weakened immune system – An imbalanced gut can weaken the immune system. This can lead to gastrointestinal infections and can present as recurring diarrhea.
  • Affect mood and behavior – Mood and behavior conditions can be a result of an unbalanced gut. These conditions range from fatigue, mood changes, irritability, anxiety, and depression.11
  • Skin conditions – Gut health can influence skin health. Imbalances in the gut microbiome sometimes cause acne, eczema, and psoriasis.11 Resolving gut issues can sometimes improve skin conditions.

Is There a Connection Between Chronic Diseases and Gut Health?

Emerging research suggests a connection between gut health and chronic diseases. Most studies have been done on animal subjects, so there’s nothing definitive yet.

However, growing evidence examines associations between an unhealthy gut and various chronic conditions. Some examples include:

  • Cardiovascular disease – The gut microbiome may influence heart health. It’s linked to conditions, like heart failure, atherosclerosis, hypertension, myocardial fibrosis, myocardial infarction, and coronary artery disease.13
  • Autoimmune conditions – These include systemic lupus erythematosus, rheumatoid arthritis, and multiple sclerosis. An unhealthy gut can trigger an immune response. This response leads to chronic inflammation and autoimmune reactions.14
  • Metabolic disorders – Dysbiosis in the gut microbiome has been linked to metabolic disorders. Examples include type 2 diabetes and obesity.15 Imbalances in gut bacteria can affect insulin sensitivity and glucose tolerance.
  • Inflammatory bowel disease (IBD) – Chronic inflammation in the gastrointestinal tract can cause conditions like ulcerative colitis and Crohn’s disease.16

How Can You Starve Bad Bacteria in Your Gut?

Maintaining a healthy gut involves promoting the growth of beneficial bacteria. It also involves limiting the proliferation of bad bacteria. One effective approach to achieving this is by "starving" the bad bacteria. 

“One must maintain the balance between good and bad bacteria. Decreasing the power of bad bacteria enables them to remain non-pathogenic,” explains Dr. Mira.

Diet and lifestyle changes can create a gut environment that is less favorable for harmful bacteria.

The Role of Diet in Starving Bad Bacteria

Diet plays a crucial role in shaping the composition of the gut microbiome. A diverse and balanced diet can limit the growth of bad bacteria. It can also promote the growth of beneficial bacteria.

Here are key dietary strategies to consider:

  • Increase fiber intake – Fiber-rich foods provide prebiotics that nourish beneficial bacteria. Insoluble fibers act as food for good bacteria. Include fruits, vegetables, whole grains, legumes, and nuts in your diet.
  • Consume fermented foods – Fermented foods are rich in beneficial bacteria known as probiotics.17 These live microorganisms can help restore and maintain a healthy gut microbiome balance. Consider incorporating consuming more yogurt, kefir, sauerkraut, kimchi, and kombucha.
  • Limit sugar and refined carbohydrates – Bad bacteria thrive on sugar and refined carbohydrates.18 Excessively consuming these foods can lead to dysbiosis and an overgrowth of harmful bacteria.
  • Moderate alcohol consumption – Limit alcohol intake or opt for healthier alternatives. These include non-alcoholic fermented beverages or herbal teas.
  • Stay hydrated – Drinking an adequate amount of water is crucial for maintaining a healthy gut. Water helps in digestion, nutrient absorption, and the elimination of waste products.

Lifestyle Factors Affecting Gut Bacteria

In addition to diet, several lifestyle factors can impact the health of your gut bacteria. Here are some key considerations:

  • Regular physical activity – Exercise can enhance gut flora diversity. It can also promote the growth of beneficial bacteria.
  • Prioritize quality sleep – Avoid disrupted sleep patterns and chronic sleep deprivation. This can negatively affect the gut microbiome.19
  • Manage stress levels – Chronic stress can disrupt gut balance and cause gut inflammation.20 Practice stress-management techniques. Consider practicing mindfulness, meditation, deep breathing exercises, and activities that promote relaxation. This can help support a healthy gut.
  • Avoid unnecessary antibiotic use – Antibiotics are necessary for treating bacterial infections. However, they can also disrupt the gut microbiome. They do this by killing both harmful and beneficial bacteria.21 Only use antibiotics when prescribed by a healthcare professional and follow the recommended dosage.

What Foods Help Eliminate Bad Gut Bacteria?

Certain foods possess antimicrobial properties that can help in this process. Incorporating these foods into your diet can contribute to a healthier gut microbiome:22

  • Garlic – Garlic can control bad bacteria and maintain yeast in the gut. Its properties fuel bacteria by improving their performance to overall gut health.
  • Ginger – Ginger stimulates stomach acid production. It also allows the digestive system to move food through the gut. You can add freshly grated ginger to soups or stir-fries or create homemade ginger tea.
  • Turmeric – Turmeric contains curcumin, a compound with antimicrobial and anti-inflammatory properties.23 It promotes the absorption of nutrients in the gut. Consider including turmeric in your meals or taking it as a supplement.
  • Cranberries – Cranberries contain compounds that prevent pathogens from  adhering to the gut lining.24 Consuming cranberries or cranberry juice can contribute to a healthier gut environment. Avoid cranberry juices that are high in sugar.
  • Berries – Berries are rich in nutrients, antioxidants, and fiber.25 These components eliminate bad gut bacteria and promote a diverse and balanced microbiome. Consider consuming more berries such as strawberries, blueberries, and raspberries.

The Power of Probiotic Foods

How to Starve Bad Gut Bacteria 4

Taking probiotic supplements can support digestive health. However, many foods also contain healthy probiotics.

Probiotic foods are those that contain live beneficial bacteria. They can directly contribute to a healthy gut microbiome.6 These foods introduce good bacteria into the gut, promoting microbial diversity and balance.

“Most natural probiotics come from fermented food. Fermentation also creates important enzymes, vitamins, and fatty acids,” explains Dr. Mira.

Here are some examples of probiotic-rich foods:22

  • Yogurt – Yogurt is a well-known probiotic food. It contains live cultures of beneficial bacteria. This can help restore and maintain a healthy gut microbiome. Be sure to avoid yogurts that are high in sugar.
  • Kefir – Kefir is a fermented milk beverage that contains a variety of beneficial bacteria and yeast strains. Consuming kefir can introduce probiotics into the gut and support gut health.
  • Sauerkraut – You can make sauerkraut by fermenting cabbage. It provides probiotics and contribute to a healthy gut environment. Consider including sauerkraut into your diet. 
  • Kimchi – Kimchi is a traditional Korean dish made from fermented vegetables, primarily cabbage. It contains fiber and vitamins that are also beneficial for gut health. 
  • Kombucha – Kombucha is a fermented tea beverage that contains a variety of probiotic good bacteria. Adding kombucha to your diet can introduce probiotics and support a diverse gut microbiome.

The Benefits of a Plant-Based Diet

Animal products like red meat or other processed foods inhibit good bacteria growth. They can also enhance bad bacteria linked to chronic diseases.26

A plant-based diet consists of fruits, vegetables, whole grains, legumes, and nuts. It can provide numerous gut health benefits.26

Here's how a plant-based diet can contribute to gut health and discourage the growth of harmful bacteria:

  • High fiber content – Plant-based foods are typically high in dietary fiber, which acts as a prebiotic.
  • Phytonutrients – Fruits, vegetables, and whole grains are abundant in phytonutrients. Phytonutrients have antimicrobial properties.27
  • Antioxidants – Plant-based foods are rich in antioxidants.27 Antioxidants contribute to overall gut health and support a diverse and balanced microbiome.
  • Reduced inflammation – Plant-based diets often lead to lower levels of inflammation. Chronic inflammation can disrupt the gut microbiome. A diet that reduces inflammation can support a healthier gut. It can also prevent conditions such as obesity or diabetes.26

Reminders for Starving Bad Bacteria and Overall Wellness

Maintaining good gut health is essential for overall wellness. 

Adopting a holistic approach is crucial if you want to nourish your gut and encourage the growth of healthy bacteria.

Place a strong emphasis on eating a varied, balanced diet that includes a selection of fruits, vegetables, whole grains, legumes, nuts, and seeds. 

Beyond diet, other lifestyle choices can greatly impact gut health. 

Along with improving your general health, regular exercise encourages a diverse gut microbiota.

Maintaining a healthy gut environment can be accomplished using stress management techniques, including mindfulness, meditation, and relaxation exercises. 

Keep in mind that taking care of your gut is a lifetime responsibility. 

Boosting your gut health and enhancing your general well-being entails implementing these techniques and making deliberate decisions to starve bad bacteria.

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Updated on August 13, 2023
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27 sources cited
Updated on August 13, 2023
  1. Gut microbiota’s effect on physical and mental health”. European Food Information Council.
  2. Gut microbiota’s effect on mental health: The gut-brain axis”. National Library of Medicine.
  3. Can gut bacteria improve your health?”. Harvard Health Publishing School.
  4. How To Starve Bad Gut Bacteria For Better Thyroid Health”. Paloma Health. 
  5. The impact of human activities and lifestyles on the interlinked microbiota and health of humans and of ecosystems”. ScienceDirect.
  6. The Microbiome”. Harvard T.H. Chan School of Public Health.
  7. Typical intestinal bacteria”. Otsuka Pharmaceutical Co.
  8. Gut Microbiome May Help or Hinder Defenses Against SARS-CoV-2”. TheScientist.
  9. Gut Microbiota Dysbiosis: Triggers, Consequences, Diagnostic and Therapeutic Options”. National Library of Medicine.
  10. Dysbiosis of the gut microbiota in disease”. National Library of Medicine.
  11. Dysbiosis”. Osmosis from ELSEVIER.
  12. 11 Symptoms of Leaky Gut Syndrome”. Medanta.
  13. The Gut Microbiota (Microbiome) in Cardiovascular Disease and Its Therapeutic Regulation”. Frontiers.
  14. Gut dysbiosis in autoimmune diseases: Association with mortality”. Frontiers.
  15. Gut Microbiota and Complications of Type-2 Diabetes”. National Library of Medicine.
  16. Alteration of Gut Microbiota in Inflammatory Bowel Disease (IBD): Cause or Consequence? IBD Treatment Targeting the Gut Microbiome”. National Library of Medicine.
  17. How To Starve Bad Gut Bacteria?”. Klarity.
  18. Healthy Diet and Lifestyle Improve the Gut Microbiota and Help Combat Fungal Infection”. Multidisciplinary Digital Publishing Institute
  19. Gut microbiome diversity is associated with sleep physiology in humans”. National Library of Medicine.
  20. Stress, depression, diet, and the gut microbiota: human–bacteria interactions at the core of psychoneuroimmunology and nutrition”. National Library of Medicine.
  21. Impact of antibiotics on the human microbiome and consequences for host health”. National Library of Medicine.
  22. Gut Health Foods - 15 Foods For Good Gut Health”. Benenden Health.
  23. Health Benefits of Turmeric”. News Medical Life Sciences.
  24. Impact of Cranberries on Gut Microbiota and Cardiometabolic Health: Proceedings of the Cranberry Health Research Conference 2015”. National Library of Medicine.
  25. Evaluation of Antioxidant Capacity and Gut Microbiota Modulatory Effects of Different Kinds of Berries”. National Library of Medicine.
  26. Gut Bacteria”. Physicians Committee for Responsible Medicine.
  27. Phytonutrients”. ScienceDirect.
Dr. Rizza Mira
Dr. Rizza Mira
Medical Reviewer
Dr. Rizza Mira is a medical doctor and a general practitioner who specializes in pediatrics, nutrition, dietetics, and public health.

As a pediatrician, she is dedicated to the general health and well-being of children and expecting parents. She believes that good nutrition, a healthy lifestyle, and prevention of illness are key to ensuring the health of children and their families.

When she’s not in the hospital, Rizza advocates and mobilizes causes like breastfeeding, vaccination drives, and initiatives to prevent illness in the community.
Will Hunter
Will Hunter
Content Contributor
Will is a content writer for KnowYourDNA. He received his B.A. in Psychology from the University of California, Los Angeles. Will has 7 years of experience writing health-related content, with an emphasis on nutrition, alternative medicine, and longevity.
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