Gut bacteria, parasites and fungus- should we be alarmed by them?

It was in the late 19th Century when Scientist, Robert Koch first discovered that certain bacteria could lead to particular diseases (like cholera and tuberculosis). Then in the 1920’s, the ‘golden age’ arrived with the discovery of antibiotics and by the end of World War II, penicillin was nicknamed ‘the wonder drug’ and had saved many lives.

What followed was decades of a ‘war against bacteria’ leading us to our modern day, ultra-sanitised world. Alarmingly, we are now learning that this ‘squeaky clean’ existence may not be as helpful as we once thought and is believed to have led to an increase in health issues like: allergies, asthma and other autoimmune disorders.

Benefits of gut bacteria

So unless you’ve been hiding under a rock (in which these guys will also hang out), it’s probably likely that you now realise that not all bacteria in our body is bad. In fact, you might now know that beneficial bacteria in the gut can hugely contribute to our wellbeing, support our immune system and even improve our mood.

In fact, some good news in gut bacteria research has shown that:

  • Those who live the longest and healthiest lives (in the ‘Blue Zones’) tend to have a widely diverse gut bacteria (1)
  • Specific gut bacteria has the potential to not only improve Parkinson’s symptoms but could even protect people from developing the condition in the first place (2)
  • Treating the gut to a blend of five different friendly bacteria called ‘lactobacillus probiotics’ (combined with prebiotic inulin), could help with acute and long-term Covid symptoms (3)

However, there’s always two sides to every story, and with stool testing becoming more popular with health practitioners to identify ‘root causes’ of client’s health conditions, there’s still a fear about certain bacteria, parasites and fungus; So let’s take a closer look and see whether we need to be alarmed.

Is bad bacteria, bad news?

It would be misleading to say that all bacteria in the gut is beneficial, however stating that some can only be ‘pathogenic’ would also be incorrect.

For example, even though we know Gram Negative bacteria can cause issues because they release lipopolysaccharides (LPS) which trigger inflammation; in small amounts, these too can remain harmless to us, the host. This means, that just because they are there, it doesn’t necessarily mean alarm bells…

Surely all parasites are bad?

When we think about parasites we can often be transported to horror stories we have heard in the news like ‘brain eating organisms’ and even how ‘deadly parasites can burrow into the body through bare feet’. Unsurprisingly, this fearmongering can lead to parasites becoming an immediate enemy and are often targeted quickly with things like strong anti-microbials.

However, new research has shown that actually, like bacteria, there could be beneficial aspects of having some parasites. For example, a common parasite named Blastocystis hominis (B. Hominis) which previously was believed to lead to IBS symptoms, has now been found to be present in similar amounts amongst patients with gut complaints and those without (4).

In fact, this parasite has even been found to be beneficial in some cases by stimulating mucus production in the gut, which can relieve symptoms of colitis and improve gut health (5). This obviously goes hugely against initial thinking and worry about having a parasite.

Fungus cant be fun?!

Another member of the gut community is the yeast/ fungal part of the team. One yeast (a type of fungus), that often gets a lot of the limelight is ‘Candida Albicans’. This is an opportunistic yeast that although can be part of a healthy gut environment, if left to overgrow in the right environment, can cause a variety of issues like low mood and IBS. However, an overgrowth of Candida only usually happens when there are issues already within the gut, like low secretary IgA (that can compromise immunity). This is why, restrictive diets like sugar detoxes (with no other thought to the larger gut environment) will often only be a temporary fix to symptoms.

In other fungal news, Saccharomyces boulardii (S Boulardii) is making positive waves in the wellness space with the yeast being linked to protecting the gastrointestinal lining, reducing diarrhoea issues and even rebalancing the gut bacteria after anti-biotic use!

Still alarmed?

So all, in all, the majority of gut bacteria, parasites and funguses can be a healthy part of a gut environment. Health and gut issues often only arise when there’s a dysfunction in the gut environment that causes an overgrowth of certain organisms. This will then impacts the delicate balance that usually exists. Therefore, rather than being alarmed (as stress can impact the balance!), it’s much better to focus on the bigger picture of gut health by:

  • Promoting gut diversity through consistently eating a colourful and fibre rich diet
  • Remaining optimally hydrated to reduce issues like constipation triggering imbalances
  • Ensuring you have adequate levels of hydrochloric acid, digestive enzymes and bile to properly digest food and restrict any unhelpful overgrowth (stool testing can be helpful to identify this!)

  • Valdes, A et al., (2018). Role of the gut microbiota in nutrition and health. BMJ, p.k2179.
  • Infectious Diseases Diagnosis & Treatment, 2021. The Influence of a blend of Probiotic Lactobacillus and Prebiotic Inulin on the Duration and Severity of Symptoms among Individuals with Covid-19. 5(1).
  • Liu, J et al., (2020). Gut Microbiota Approach-A New Strategy to Treat Parkinson’s Disease. Frontiers in cellular and infection microbiology10, 570658.
  • Feldman, M., Friedman, L. S., & Brandt, L. J. (2020). Sleisenger and Fordtran’s gastrointestinal and liver disease: Pathophysiology, diagnosis, management.
  • Lepczyńska M,et al., (2017): how do specific diets and human gut microbiota affect its development and pathogenicity? Eur J Clin Microbiol Infect Dis. ;36(9):1531-1540. doi: 10.1007/s10096-017-2965-0. Epub 2017 Mar 22. PMID: 28326446; PMCID: PMC5554277.