There are trillions of bacteria, viruses and other microorganisms that live, flourish and die in our gut. These microorganisms are naturally present in our bodies and play a crucial role in our physiological functions and overall health.
Probiotics are the "good bacteria" that digest food, absorb nutrients and fight infections. They are also found in certain foods and supplements, such as yogurt and other fermented foods.
The environment these microorganisms live in is referred to as a "gut microbiome", with each individual's being as unique as their fingerprint. A healthy gut microbiome is characterised by a diverse array of beneficial bacteria, and probiotics can help to promote the growth and balance of these bacteria, which is essential for overall wellbeing.
Types of Probiotics
Though there are countless strains of live bacteria in your gut, some are commonly available for purchase in product form.
Lactobacillus: This is the most commonly used probiotic. It's found in many fermented foods like yogurt, kefir, and sauerkraut. Lactobacillus can help to break down carbohydrates, such as lactose, which is a sugar found in milk.
Bifidobacterium: This probiotic is found in the large intestine and is known for its ability to fight off harmful bacteria.
Saccharomyces boulardii: This is a yeast-based probiotic that can help to prevent diarrhea and other gastrointestinal problems. It's commonly used to treat antibiotic-associated diarrhea and can be found in supplement form.
Streptococcus thermophilus: This probiotic is commonly found in yogurt and other fermented dairy products. It can help to improve lactose digestion and support the immune system.
Bacillus coagulans: This is a spore-forming probiotic that can survive harsh conditions like the acidic environment of the stomach. It's commonly found in supplement form and has been shown to help improve digestive health.
Food Sources of Probiotics
For most people, taking a probiotic supplement may not be necessary if they include a variety of probiotic foods in their diet. Fermented foods contain live cultures and are rich sources of probiotics. They may also be easier to digest as they are partially broken down.
Nutrition professionals often recommend consuming at least one serving of fermented foods per day as part of a balanced diet. Here are some fermented foods that are both easy to access and taste delicious:
- Yogurt Kefir (milk)
Probiotics are measured in colony-forming units (CFU), which indicate the number of cells. This information may be displayed on the back of a pack so you can gauge a products probiotic content. However, it’s important to note that a higher number of CFU does not necessarily mean more health benefits.
Health Benefits of Probiotics
Improving Digestive Health
One of the primary benefits of probiotics is their ability to improve digestive health. The gut microbiome, which is the community of microorganisms that live in the gut, plays a crucial role in digestion and nutrient absorption. A healthy gut microbiome is characterised by a diverse array of beneficial bacteria, and probiotics can help to promote the growth of these bacteria.
By restoring the balance of gut bacteria, probiotics can help to alleviate symptoms of conditions such as irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). Additionally, probiotics may help to prevent antibiotic-associated diarrhea, a common side effect of antibiotics.
Probiotics have also been found to have a positive impact on the immune system. Studies have shown that certain strains of probiotics can help to reduce inflammation in the body. Inflammation is linked to a range of health issues, including cardiovascular disease, arthritis and diabetes. By reducing inflammation, probiotics may help to reduce the risk of these conditions.
Boosting Immune System
The gut is home to a large number of immune cells, with it being said that as much as 70% of the immune system resides in the gut. Probiotics have been shown to have a positive effect on the system, as probiotics can help to stimulate cell production. This can improve the body's ability to fight off infections.
Mental Health Benefits
Research has also suggested that probiotics may have a positive effect on mental health. In fact, the gut microbiome is often referred to as the "second brain," as it communicates with the central nervous system via the vagus nerve. It’s becoming increasingly evident that the gut microbiome can influence mood, behaviour, and cognitive function.
Probiotics vs Prebiotics
While probiotics are the live bacteria that live in the gut, prebiotics are the non-digestible plant fibres that ferment in the gut, essentially “feeding” the beneficial bacteria. This allows it to thrive and carry out its required roles. Both pre and probiotics are essential components of a healthy body.
Prebiotics are found in a variety of plant foods such as:
- Bananas (particularly unripe)
Choosing the Right Probiotic
When it comes to choosing a probiotic supplement, it's important to consider the specific strains of bacteria included in the supplement. Each strain may have different health benefits, so you may need to research which type is best for your condition. And, as we always recommend, it's best to consult your GP before adding any supplement to your regime.
It's also important to choose a high-quality supplement from a reputable manufacturer. Look for a supplement that has been third-party tested for purity and potency, and choose a supplement that contains enough colony-forming units (CFUs) to make an impact.
Probiotics are a crucial part of a healthy diet as they support many digestive and physiological functions. Adding a probiotic supplement to your diet may improve digestive health, mood and even your immune system. However, as always, the first step before choosing any supplement should be to consume a balanced diet rich in a variety of fruit and veg.
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Harper A, Naghibi MM, Mayo Clinic. (2021). Probiotics. https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/probiotics/faq-20058065
Harper A, Naghibi MM, National Center for Complementary and Integrative Health. (2021). Probiotics: In depth. https://www.nccih.nih.gov/health/probiotics-in-depth
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