Bacteria in Your Gut: Good or Bad?

Did you know more bacteria lives on your than the number of cells you have? Crazy, right!

So, why do we have so many and are they good or bad?

The bacteria that live on and inside of you are part of your normal human microbiota, which is a varied group of microorganisms. They are not bad, in fact, they help us.






Image 1: Streptococcus Staphylococcus by CDC via Unsplash

Image 2: Clostridium sp. Organisms by CDC via Unsplash


What is the gut microbiota? 

The gut microbiota is made of trillions of micro-organisms but is mostly comprised of bacteria that live inside your intestinal tract and are with you from birth to death. The gut microbiota within each individual is unique and contribute heavily to a range of different things such as our immunity, metabolism and much more.

Humans have evolved to work together, in a mutualist relationship, with these micro-organisms which provide us with a wide range of benefits.

Why is gut health important and how does it affect your body?

Your gut microbiota plays an important part in a wide range of physiological processes, particularly your nutrition and immune defences.

As shown below, your gut microbiota is interlinked with diet and the immune system.

Image by Laura Quintero (Author)


Immunity: The gut immune system is closely associated with the appearance of gut microbiota. This is because of the commensal relationship between bacteria and your gut, our waste products are food for them. Micro-organism allows for the stimulation of the immune system and also protects against pathogens, which are organisms that cause disease and make you sick.

Nutrients: The gut microbiota is critical in the digestion of food because they process nutrients and break food down to allow nutrients to become available to your cells. This is due to the commensal relationship between bacteria and your gut as the micro-organism can use the food we ingest and do different and important things with it, such as synthesize essential molecules, break down plant fibres in food to allow the release of small molecules that can be used in metabolism, enhance our digestive efficiency by degrading polysaccharides (a type of carbohydrate) which increases metabolism. Therefore, they play a valuable role in metabolism and energy maintenance and have even been associated with providing metabolic pathways for food to break down.

Why should you pay attention to your gut health?

Whilst the gut microbiota within everyone is different, there have been patterns identified in what healthy and unhealthy individuals have in their gut.

Dr Gail Hecht, chair of the American Gastroenterological Association Center for Gut Microbiome Research & Education, states that “in an unhealthy individual, there’s much less diversity, and there seems to be an increase of bacteria we associate with disease.”

Therefore, changes in diversity and the number of micro-organisms in your gut microbiota can lead to infection and disease.

Dysbiosis, which is a reduction in microbiota diversity, can have many direct and indirect associations with disease. Disease may be caused by pathogens ‘invaders’ or your gut microbiota. Indirect associations include obesity, inflammatory bowel disease (IBS), allergies, autoimmune disease, undernutrition and many other things. The most common cause of dysbiosis is the use of broad-spectrum antibiotics.

You’re probably wondering now, I don’t want to get sick so how can I improve my gut health?

Unsurprisingly, many things may affect gut health. If you want to maintain or even improve your gut health you should try some of the ideas listed below.

  • Adequate sleep
  • Regular exercise
  • Eat a diverse range of foods
  • Eat fermented foods
  • Limit your intake of artificial sweeteners
  • Eat prebiotic foods
  • Eat whole grains
  • Try a plant-based diet
  • Take a probiotic supplement
  • Only take antibiotics when necessary

The bottom line is to follow a healthy diet and lifestyle.

If it is beneficial for the rest of your body, it is probably good for your gut.

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4 Responses to “Bacteria in Your Gut: Good or Bad?”

  1. helenap says:

    Thanks for this informative read Laura! I really enjoyed reading about gut health and how the number and types of bacteria in the gut seem to be correlated with certain diseases! This is an ever-expanding field and so much cool research is being done into it now. It’s sort of mind-boggling (and slightly freaky) to think about how much bacteria exist in our gut, but if I remind myself that they’re helping with my immune system and digestion, I’ll feel slightly better about it.

  2. Ashqkein Kang says:

    Very insightful read Laura! I didn’t know that our gut bacteria had so many implications and benefits for us! Thank you for providing this information in an easy to read, engaging manner 🙂

  3. David Tang says:

    Hi Laura,
    Gut health is super important! Our bacterial microbiota is essential for fighting against infections and diseases. It needs to be addressed more, especially during this time of year where most of us are in lockdown!

  4. Lily Ahlemeyer says:

    Hi Laura,

    I’ve really enjoyed digesting this information, thank you. Especially the gut health tips at the end. I was just wondering, what do artificial sweeteners do to our guts?