Prebiotics and probiotics - what are they?

Probiotics and prebiotics. With both words set apart by just a single differing letter, it’s no surprise that they are so commonly confused.

As you may know, they both relate very closely to the health of our guts; which, in turn, relate very closely to our overall health.

But what are they? Where do you find them? And how can they help you improve your gut health?

Let’s take a look at them side by side.



Out of the two, probiotics probably receive more attention by the mainstream health media.

Put simply, a probiotic containing food or supplement is something that contains live bacteria that are beneficial for our gut health.

Most people now associate probiotics with little bottles of drinking yoghurt and expensive supplements; however, right the way throughout our evolution, almost every traditional society has unwittingly consumed probiotics through fermented foods.

It turns out, these fermented foods may well be the missing link in our diets today. And, as such, this missing link is the reason that so many of us are now taking probiotic supplements to maintain a healthy digestive system.

The human race have evolved eating fermented foods; before the days that pineapples could be shipped in from Costa Rica throughout the year, traditional societies preserved their seasonal produce using methods of fermentation. Not only did this method mean that they could enjoy seasonal vegetables such as cabbage, beets and carrots year round, it actually enhanced the nutritional profile of the food, with the content of certain vitamins (particularly B vitamins) proven to be much higher in fermented foods than their fresh equivalent.

Fermenting foods also saw the production of digestive enzymes, which when eaten as part of a meal, assisted in the breakdown of the other foods that it was eaten with. And of course, most notably, probiotics were formed; the beneficial live bacteria that ensure our digestive system is able to properly break down and absorb the food that we eat.

Unfortunately, as we have evolved and fresh produce is now available year round, our need for fermentation has all but vanished. Our digestive system’s need, however, has remained the same – one of the most notable reasons that so many of us are lacking in good bacteria.

probiotics food diet


More about fermented foods

Recent awareness of the benefits (and amazing taste!) of fermented foods has seen a rapid growth in their availability.

Delicious sauerkrauts and kimchis are popping up in the refrigerators of health food shops, whilst probiotic rich beverages such as kombucha and kefir are becoming the latest ‘superdrinks’ loved by nutritionists and celebrities alike. When buying fermented foods like sauerkraut, make sure you are doing so from the refrigerator section, and that it says ‘unpasteurised’ or ‘raw’ on the jar. You can find long life pickles and sauerkrauts on the shelves, but these have been pasteurised, meaning all of the beneficial bacteria have been lost.

Even better, why not make your own? They are incredibly simple and cheap to do; all you need is some vegetables, some water, some salt and an air tight jar to get started. Fermented beverages are a little more difficult and require a ‘started culture’ to get going – but if you have the time and patience, there are plenty of recipes out there!

If time, lack of availability or a dislike of the taste mean that you can’t get on board with fermented foods, then taking a high quality probiotic is highly advisable, especially if you suffer from any kind of digestive complaints.

Look for one with multiple strains of bacteria, as this will help ensure that you have a diverse gut population that more accurately replicates one of our ancestors. And, if by now you haven’t already heard of some of the amazing benefits that a healthy gut bacteria offer, we’ll list our favourites:

  • Improved digestion
  • Better mood (less mood swings and irritability)
  • More balanced blood sugar
  • Greater metabolic conditioning
  • Clearer skin
  • More mental clarity
  • A stronger immune system
  • Greater energy
  • Reduced (or completely removed) symptoms of IBS

In fact, our gut bacteria support virtually all aspects of our health. Without them, we couldn’t survive – it’s that simple.

Now we know what the gut bacteria do for us, let’s examine what we can do for them. Enter, prebiotics.



So you’ve loaded up on sauerkraut and kombucha, you’re eating Greek yoghurt (or dairy free equivalent) regularly, and you’ve added a high quality probiotic to your daily diet. You’ve got a wide range of good bacteria making their way into your colon; but in order for them to thrive, they’re going to need feeding. Think of it as having your own little farm; if you want your livestock to thrive, you’ll need to give them the best food that you can. This food is commonly referred to as a ‘prebiotic.’

Prebiotics are the fuel that allow our beneficial gut bacteria to thrive. Thankfully, prebiotics are found packaged in some very delicious foods, and if you eat your fair share of fruits and vegetables, you’ll probably be eating them without knowing it.

Soluble fibre is an excellent prebiotic; think potatoes, sweet potatoes, squash, yams, bananas, or most other starchy fruits and vegetables. Then there’s inulin and oligofructose, found in onions, garlic, leeks, chicory, Jerusalem artichoke and asparagus. And finally, resistant starch, found in cooked and cooled potatoes, beans and other legumes, and green bananas.

Whilst highly nutritious to humans, all of these foods have a very small portion that our own digestive systems do not break down; our gut bacteria feed on it instead. This provides them with the energy that they need to carry out their everyday functions, from regulating our immune system to helping us absorb nutrients from food. Good news for them, and as we discussed earlier, good news for us, too.

Besides eating prebiotic containing foods (which you should be doing anyway), other things we can do to support our gut bacteria include regular exercise and managing our stress levels. Turns out, they’re very sensitive creatures, and when we get stressed out, they do too. Ever felt ‘butterflies’ in your stomach when nervous? This just shows how closely linked our guts and our brains are, with many doctors and nutritionists often referring to the ‘gut-brain’ axis when treating patients with mental illnesses such as depression, autism or schizophrenia.


What to do?

A healthy gut is the gateway to a healthy body. And a healthy population of gut bacteria is the gateway to a healthy gut.

Want a healthy population of gut bacteria? Consume probiotics regularly; either in the form of fermented foods, or as a probiotic supplement. Ideally, do both, as greater variety leads to a more diverse microbiome and greater digestive capacity. And to support them, eat plenty of prebiotic containing foods like sweet potato, squash, bananas, onions, garlic, beans and peas. Want a little morale boost in your quest for healthy gut flora? Dark chocolate is a prebiotic too.