Blastocystis: Microbiome Friend or Foe?
Blastocystis is a common protozoa (parasite) that can be transmitted through water, food, human or animal faeces. It is often identified as the most common eukaryotic organism reported in human faecal samples. Many individuals that have this parasite can be asymptomatic, whilst others can present with an array of gastrointestinal symptoms such as diarrhoea, nausea, bloating, vomiting and abdominal pain. If an individual presents with gastrointestinal symptoms and a stool sample reveals that Blastocystis is present, it is often treated with antibiotics, or if you see a naturopath, with dietary interventions and/or herbal medicine, in an attempt to eradicate this stubborn parasite.
For decades Blastocystis has been controversial, as despite the many studies done on this organism it has never been determined if it is pathogenic or commensal. (Commensal refers to microbes that can be present within the digestive tract but not harmful, and may actually have some benefits of being present).
One recent study completed tested over 1000 individuals from various geographical regions of the world to see if Blastocystis was present or not. It was observed that those that tested positive for Blastocystis had a greater bacterial diversity than the individuals that tested negative for the parasite, and also reported that Proteobacteria (a type of bacteria that has been associated with gut permeability and increased risk of diseases such as inflammatory bowel disease (IBD) and metabolic disorders) were 1000-10,000 times higher in individuals that tested negative for Blastocystis than those that were positive.
The results suggest that the presence of Blastocystis may actually be beneficial, possibly being an active driver of gut microbiota diversity and host metabolism.
So what does this mean in terms of treatment? If a positive Blastocystis sample is returned, and other pathology has been ruled out, a comprehensive stool analysis can provide more insight as to what other pathogenic bacteria, parasites or GIT inflammatory markers that may be present, possibly contributing to your gastrointestinal symptoms.
Whilst more research is needed to establish if Blastocystis is a biomarker of intestinal eubiosis, it has been well established that a higher microbiome diversity is beneficial to gut health. By including a diet that is varied, and contains in particular daily intake of prebiotic and probiotic foods, we can assist in re-innoculating and correcting bacterial imbalances that may be present within the gut, and decrease inflammation.
Ways to increase microbiome diversity:
Prebiotic foods: Prebiotic foods are sources of dietary fibre, that are resistant to digestion until they reach the large intestine. They are responsible for healthy bowel function including aiding in regular and complete bowel movements, act as a substrate for short chain fatty acid (SCFA) production, assist with regulating insulin response, improving mineral absorption and encouraging the growth of beneficial bacteria. They provide the foundations for probiotic foods to improve gut health, and help to reduce gut permeability. Prebiotic foods include: Garlic, onions, leeks, green or slightly green bananas, lentils, chickpeas, beans, Jerusalem artichoke, berries, oats, asparagus, flaxseeds, barley, dandelion greens, cacao, cashews, pistachio nuts and resistant starches such as cooked and cooled potatoes. Prebiotic foods should ideally be consumed with each meal of the day.
Probiotic foods: These foods contain strains of beneficial bacteria and yeasts that can help to re-innoculate the bowel and increase presence of beneficial strains of bacteria: Sauerkraut, kimchi, milk kefir, coconut water kefir, kombucha. To maintain colonisation within the digestive tract, probiotics must be consumed regularly i.e. daily. Probiotic foods are easy to make yourself and are not too time consuming, and unless purchasing a high quality probiotic food/beverage are less processed, less pre-packaged, and contain a higher therapeutic dose of bacterial strains than store bought. If you have not made probiotic foods before I recommend to start with sauerkraut or a kefir such as milk or coconut water kefir.
Get your veggies! A diet high in saturated fats and meat products have been found to lead to increased inflammation and less microbiome diversity than those who have a vegan or vegetarian diet. When consuming meat aim for organic, grass fed and local options where you can, and keep to around 2-3 serves per week. Consuming a diverse range of in particular fruit and vegetables (including fresh and dried herbs and spices) will assist with increasing various beneficial strains of bacteria present within the gut.
Limit alcohol consumption: Alcohol can increase bacterial overgrowth particularly in the small intestine, changing the composition of the bacteria present within the gut. It also increases intestinal permeability and oxidative stress, increasing systemic inflammation. Not to mention that it is a class 1 carcinogen - which means it is known to be implicated with many cancers, as well as auto-immune conditions, cardiovascular disease and mental health to name a few. I encourage patients to be having at least 4-5 alcohol free days per week, and drink in moderation when doing so.
Intermittent fasting: Studies are suggesting that intermittent fasting can promote microbiome remodelling and increase microbiome diversity, improve the production of bacteria that can change the type of fat we store/carry which can assist with improving metabolic health outcomes, move microbes away from the lining of the gut which can enhance glucose regulation, and when fasting is done for certain periods of time it can regenerate stem cells that can repair the gut lining.
Manage stress: Research conducted around the effects of stress on the microbiome suggests that it may modify the commensal microbiota within the gut, decrease short chain fatty acid production (SCFAs are metabolites produced in the colon by the fermentation of dietary fibre, and are believed to play a role in endocrine, metabolic and immune health), increase intestinal permeability and increase presence of pro-inflammatory bacteria. Lifestyle strategies such as exercise, mediation or relaxation practices (this can be reading, listening to music, gardening - nothing with screens!), proper sleep and a healthy diet can assist with stress management, and ideally should be practiced daily.
References:
PMID: 35208781
PMID: 29230419
PMID: 28326446
PMID: 26695747
