Probiotics are a community of healthy bacteria that reside within the gut. They have a variety of roles including maintaining gut balance, immune function and metabolism.
Probiotics are found in food and supplement form, which can help support the bacteria that live inside the gut, especially when challenged by antibiotics, poor diet, stress or travelling.
Why is the gut microbiota important?
The complex network of live bacteria, cells and nutrients that reside within the gut is known as the gut microbiota. Most the gut microbiota is found in the large intestine and is unique to each person.
The gut microbiota is often referred to as the “forgotten organ” as it resembles similar metabolic activities that other organs conduct (1). It is becoming increasingly recognised that having a healthy gut microbiota is essential for optimal health and reducing the risk of disease (2).
Probiotics support the gut microbiota and whole-body health in a variety of ways. When these healthy bacteria feed on and ferment fibre in the gut, this produces short-chain fatty acids like butyrate, propionate and acetate (3,4) This helps to provide energy and food for cells in the lower digestive tract (2,3,4).
Probiotics can also assist in building up the mucosal lining of the digestive tract, helping to defend the body against toxins and pathogens (2). They are also involved in nutrient absorption and synthesising vitamin K and B vitamins (5,6). They also help to minimise the growth of harmful bacteria by competing with it and lowering the acidity of the gut (5).
The gut microbiota is highly responsive to diet, and studies show that poorly balanced gut microbiota is linked to numerous diseases (6,7,8).
What benefits do probiotics have?
Studies have indicated that these healthy bacteria may have a role in improving symptoms and reducing the risk of different diseases.
Areas that they may assist include:
- Reducing antibiotics-associated diarrhoea (9)
- Prevent and treating vaginal infections (10)
- Managing weight (11)
- Reducing psychological distress (12)
- Improving constipation (13)
- Improving depression (14)
- Reducing abdominal pain in Irritable Bowel Syndrome (15)
- Improving cognitive function (16)
- Alleviating symptoms of a cold (17)
- Improving gut health after taking antibiotics (2)
Where are they found?
Probiotics are found both in fermented foods and in dietary supplement form. Consuming these foods is beneficial in improving the gut microbiota. Research has shown the composition of the microbiota can change within 24 hours of changing the diet.
Foods rich in probiotics include:
- Sourdough bread
- Miso soup
Which is the best probiotic to choose?
There are billions of strains of these healthy bacteria, all linked to improving different diseases or symptoms. Probiotics fall into different groups, which compromise of different specifies, with each species having many strains. The two most common groups include Lactobacillus and Bifidobacterium. When choosing a supplement, it is important to find a product containing a strain that have demonstrated the health benefit that you are seeking.
Lactobacillus acidophilus is a strain from the Lactobacillus family. Studies have shown this particular strain to reduce LDL or “bad cholesterol levels, reduce diarrhoea, and improve bloating in people with Irritable Bowel Syndrome (15,16,17,18,19).
Bifidobacterium lactis, from the Bifidobacterium family has been linked with improving the immune system, reducing the impact of a heart attack, improving glucose tolerance increasing gut transit time (20,21,22).
What are colony forming units?
Colony forming units (CFUs) are the number of viable probiotic cells within a supplement. Products with “live active cultures” have organism that are alive, whereas freeze-dried products have organisms that “come alive” in their inactive form. A properly labelled supplement should list the number of CFUs the product will contain at the “best by” date. A product with a larger dose or more strains is not always better. The best dose is one that demonstrates benefits in humans, is taken daily, and has an effective dose range of CFU from 100 million to several trillion (23).
Are probiotics safe?
Research into probiotics and gut health is still emerging and everything is not fully understood about their effectiveness and impact. Probiotics are currently labelled as safe for most people including children and pregnant woman. However, the bacteria are often grown using milk protein and individuals with milk allergy should be wary of supplements as they may contain milk protein. If you have a health condition or disease, it is important to speak to your doctor first before commencing a supplement.
Tips to maintain a healthy gut microbiota
Studies suggest that a poorly balanced gut, known as dysbiosis, can increase the levels of bad bacteria and increase negative activities of gut bacteria. To maintain optimal gut microbiota, it is important to consume a range of probiotics and prebiotics each day. This can be achieved through food, or the use of a Vitable probiotic supplement which can help support levels of good bacteria, helping to support digestive health. In addition to this, it is important to exercise, eat a variety of fibre-rich food each day and only take antibiotics when needed.
Find out more about other areas that the above supplements can help you with:
*Always read the label. Follow the directions for use. If symptoms persist, talk to your health professional. Vitamin and/or mineral supplements should not replace a balanced diet.