Gut bacteria, defender of our health

It all starts with our gut. While we are born with a sterile gut, we wouldn't have survived very long. Nature has designed us in such a way that the birthing process results in the ingestion of bacteria from our mother's vaginal flora which soon multiply to 10 times more than the number of our body's cells that reside in the gastro-intestinal tract, mouth, vagina and skin. Studies show that without these bacteria, our immune system would not be able to function. This has been demonstrated in caesarean-born babies who are more susceptible to infection and allergies.

The gut flora is made up of several hundred species and not all have been identified. The species are made of potential pathogens and beneficial or friendly bacteria that include Bifidobacteria, Lactobacilli, Ruminococcus, Bacteriodes, Eubacterium, Fusobacteria, Peptococcaceae and Streptococcus. It seems that the immune system in the gut at infancy tolerates these bacterial species and their composition pattern similarly to our mother's gut flora as the vagina is typically colonised by the bacteria from the colon. As the defender of our health, these beneficial probiotic bacteria are known to lower cholesterol, boost immunity, alleviate lactose-intolerance symptoms, prevent diarrhoea (especially traveller's diarrhoea), shorten the duration of diarrhoea, regulate bowel movements and inhibit growth of bacteria that produce cancer-causing nitrates.

It appears that after this initial colonisation, the composition of an individual's gut flora remains pretty constant throughout life. However the composition of the gut flora can be disturbed by unhealthy diet, surgery, use of antibiotics, oral contraceptives, chronic stress and poor lifestyle habits. The most common cause of dysbiosis (imbalance of intestinal bacteria) is broad-acting antibiotics that simultaneously kill both harmful and beneficial bacteria that reside in our digestive tract, mouth, vagina and skin, thus leaving those including parasites, yeasts and viruses that are resistant to the antibiotic used to flourish.

The imbalanced or disturbed gut flora means that the harmful bacteria far exceed the beneficial ones which can bring on discomfort, diarrhoea, ill-health and diseases. While most of us can recover fairly easily from a single round of antibiotic treatment, repeated usage even for those with strong constitutions will result in them having difficulty in regaining a healthy gut flora balance quickly. Daily consumption of probiotics after treatment with antibiotics is one way to maintain healthy friendly flora colonies.

As the composition of the gut flora cannot be permanently changed, research indicates that a good probiotic supplement must be able to colonise temporarily in order to induce health benefits. Hence a probiotic supplement must contain live viable bacteria that can survive stomach acid and bile as well as the ability to attach to the gut lining. By definition, they also must be specific strains of human origin and have some health-promoting benefits proven by clinical studies when consumed in adequate amounts.

Scientific evidence shows that specific strains of probiotic bacteria such as L. rhamnosus GR-1 and L. fermentum RC-14 restore normal vaginal microflora and reduce the risk of urogenital infections when five billion CFU is consumed daily while a daily intake of four billion CFU of Bifidobacterium BB12 and L. acidophilus La5 helps to reduce the severity of atopic eczema in children. CFU means colony forming unit - the number of viable or living bacteria that can colonise the gut.