What role do they play?
In Part 1 we explored where gut bacteria and probiotics actually come from and how they originally get to populate our digestive tract. In this section we will look at what their actual role is and how they support the body.
For starters, we need to understand that a person’s gut microbiome (or bacterial blueprint) is unique to them, kind of like a fingerprint. There is some evidence to show that if this microbiome is wiped out (such as with antibiotics), it never fully recovers back to its original state! Also there is evidence to show that the population of gut bacteria can be transient and changing. Now remember that gut bacteria supports the digestive tract’s function and well being – when the wrong bacteria are inhabiting the digestive tract we can be in trouble with diarrhoea, constipation, smelly bowel motions and gas, bloating, difficulty digesting foods, feeling nauseous…as just a few examples of gut bacterial imbalances – so we know how important a healthy gut flora is to us. And don’t forget that bacteria also inhabit the vagina keeping it healthy and pH balanced, hence the vaginal microbiome is equally important for health and wellbeing.
But what exactly is the bacteria’s role in the digestive tract and how does it support us with our health?
The bacteria in our digestive tract play many different roles. For starters, many of them help with digestion – specifically, their role lies in the fermentation of non-digestible substrates like dietary fibres and intestinal mucus. They break down fibres, starches and sugars by producing certain enzymes that ferment these nutrients. This fermentation process supports the growth of other good bacteria which then produce SCFAs (short chain fatty acids) such as butyrate – which is the main energy source of our own digestive tract cells. Essentially this is the symbiotic relationship that we have with the gut bacteria – we feed and house them and feed us back and so we have team work!
But far bigger roles than digestion, our gut bacteria play roles in:
modulating our immune system
supporting our metabolic health and weight
and also affecting our neuro-behavioural traits or moods and cravings
…and this is just naming a few key areas they are involved in. For example, the composition of our gut microbiome can either negatively or positively influence our immune system – the wrong kind of bacteria can communicate with our immune system to have an excessive reaction such as in the case of allergies (hayfever, eczema, asthma etc), and they play a key role in the aetiology of auto-immune conditions such as Chron’s disease, type 1 diabetes and coeliac’s disease to name a few. Our gut bacterial composition can also play a role in the development and progression of obesity. And the list goes one.
Are you beginning to see the crucial role these tiny bacteria can play in our health and well being?
Wait for part 3 to read about how we can help our microbiome and keep them healthy. And if you have not already had a read of this article on “Gut instinct – is it true or just your bugs talking“, enjoy it now!