Move Over Probiotics. Your Immune System is Hungry for Prebiotics (Gut health part 2)
In a nutshell:
The gut is crucial to so many aspects of our health, not least the immune system - a whopping 80% of which lies in your belly
In part one, we focussed on probiotics - live microorganisms - and how best to get these good bacteria into your gut
Now in part two we turn to prebiotics: in essence how to feed these microorganisms - so they can best serve us
This natural fertiliser comes from plants. Foods rich in soluble fire and resistant starch are great news. Processed foods and saturated fats - not so good
Heating and cooling potatoes is something to get into!
What Is A Prebiotic?
So we have a good idea of what probiotics are - and the sort of fermented and other foods which are rich in the bacteria. But prebiotics are now getting a lot of attention - for good reason.
To guide us through the gut maze, we can once again turn to gastroenterologist Dr Will Bulsiewicz (known as Dr B).
Prebiotics are, basically, a dietary fibre which feed the benevolent bacteria in the gut - and are a relatively new concept, coined in 1995.
Put simply, they are “food for the gut microbe,” says Dr B.
“What you’re doing is spreading some fertiliser on your gut microbiome so it can grow more effectively.”
When we talk about prebiotics, he explains, we are actually referring to fibre, specifically soluble fibre which can be found in plant foods. In some cases, this fibre can also apply to resistant starches - which pass through the digestive tract unchanged - which similarly comes from plant food and seem to have lots of excellent benefits.
Dr Will Bulsiewic talks us through prebiotics - why they’re so important and how to get them. It’s jolly interesting
So, What’s The Big Deal?
What makes prebiotics so important? According to Dr B, it’s the ability of these prebiotic fibres to strengthen the gut microbes which enable another crucial digestive process - postbiotics.
It’s in the colon that the gut microbes metabolise the prebiotic fibre to release postbiotics - short-chain fatty acids which he B says are “absolutely” critical for human health and especially gut health.
This process is aided by the fact that prebiotics are resistant to enzymes and gastric acid which means that these indigestible foods pass through the gut and small intestine safely and reach the colon intact. This fermentation process feeds the ‘good’ bacteria in the gut and helps grow the number of these colonies in our digestive system.
What’s The Dream Prebiotic Diet?
Can’t argue with that. So how to fill our bellies with this fabulous fertiliser?
According to Dr B, “at the end of the day, truly, the best source should be your diet”.
The right way to approach this, he suggests, is by recognising that prebiotics come from plant foods. With different plants providing different prebiotics, it’s important to have a diverse diet with a wide range of foods - as many as 30 or 40 a week ideally.
And one thing to consider: some plants have more of the gut-boosting soluble fibre than others - which get broken down to become prebiotic.
About as cute as a Jerusalem artichoke can get
The ‘Kings’ of Prebiotics: What Foods To Eat
Some popular prebiotic choices include Jerusalem artichokes, asparagus, garlic, leeks, onions and shallots. These foods all contain a natural soluble fibre called inulin.
Dr B is keen to emphasise that there are other sources of fibre other than inulin, though. One example is oatmeal.
“Oatmeal is a fantastic source of prebiotics. It has both soluble fibre and resistant starch, and both of them feed your gut microbiome.”
Other prebiotic foods getting the golden seal of approval from Dr B include seaweed and white potatoes, the latter of which Dr B thinks has been unfairly vilified.
“We behave as if there is no redeeming quality to them but if you take a potato and you heat it up and then you allow it to cool down, during that cooling process it will produce resistant starch.” Every time you heat and cool the potato, this amplifies the amount of resistant starch.
In terms of the foods your bacteria really don’t want to coming their way: processed foods and saturated fats, our gastroenterologist says.
Prebiotic Supplements: Should You Take Them?
Whilst a plant-based diet provides a rich source of natural fibre, a prebiotic supplement is still a positive addition and allows you to target a specific digestive outcome.
“When I eat whole plant foods I can’t target the microbes, I can’t target the postbiotic short-chain fatty acids. When I take the prebiotic, I can do that.”
The benefit of prebiotic supplements is the fact they are highly stable.
Unlike probiotics, they do not contain live bacteria. Instead, prebiotics contain what is known as fermentable fibre which means they are unaffected by temperature or storage and can be added to any food or drink without being altered. It also means it can pass through the gut without being affected by its acid.
Another benefit to prebiotics is that they can be used to target specific bacteria, unlike a plant-based diet which is unable to achieve this alone.
>> Five prebiotic supplements worth trying
And for those wondering whether you can take prebiotics and probiotics at the same time, the answer is yes!
Probiotics add live bacteria to your gut while prebiotics not only encourages your current gut bacteria but also the growth of new live bacteria. This is good news for your immune system which is directly benefited by this relationship between probiotics and prebiotics.
For Dr B, the benefits of prebiotics are only just beginning to show: “Prebiotics are my obsession and I think we are going to see a lot more of these in the near future.”
In part one of our gut health series, you can watch videos of:
The best explanation of the microbiome you’ll see
Whether probiotics are worth it
What the Perfect Poop tells us
Five probiotics foods your gut really wants
Screw Atkins, spuds are back
