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Prebiotics & Probiotics. What is the difference?


Scientific research now tells us that looking after your microbiome is one of the most important things you can do to protect your health. The health of your microbiome has been linked to several health complaints including irritable bowel syndrome (IBS), depression, type 2 diabetes, arthritis, allergies, Alzheimer’s disease, asthma and even weight gain. But what exactly is your microbiome? There are 100 trillion microbes, mostly bacteria, living in and on your body which let’s face it sounds pretty unpleasant. The majority have set up home in your large intestine, the lower part of your gut. The bacteria are known as your microbiota and collectively, they form your microbiome. And these guys have some important jobs to do each day. They help you digest food, protect you against pathogens (bad bugs), provide essential nutrients, enzymes and hormones; and train your immune system. Think of your microbiome as your greatest health ally. If it’s in balance you’ll experience healthy digestion, high energy, fewer illness, good mood and clear thinking. If it’s out of balance then digestive issues, low mood and low immunity can result. So what can you do to support this ally and keep them on side? A few things your gut loves include a varied diet with an abundance of brightly coloured fruits and vegetables, prebiotics and probiotics. The first is pretty self-explanatory so let’s focus on the other two.

Whilst you may have heard of probiotics, more on those guys later, prebiotics tend to be the lesser known of the two but this doesn’t mean they’re not as important. Just like us, beneficial bacteria in the large intestine need food to survive, so you need to make sure you feed them. Enter prebiotics. Prebiotics are compounds that are not digested in the small intestine, the upper part of the gut, but are instead fermented by specific types of bacteria in the large intestine. Think of them like fertilizer – they allow your beneficial bacteria to grow and multiply. Not only does this fermentation provide food for your beneficial bacteria, it also results in the production of short chain fatty acids (SCFAs). SCFAs are mainly composed of butyrate, acetate and propionate and these are the main source of nutrition for cells in your colon. This may improve the gut barrier integrity and function, and also support the immune system.

Types of prebiotics include oligosaccharides, arabinogalactans, fructooligosaccharides and inulin. These are primarily found in carbohydrates, especially those that are starchy. However breast milk is the first prebiotic we come in contact with. Then as we grow older, we rely on our diet to provide this nourishment. Prebiotics are primarily found in fibrous foods with the top sources being Jerusalem artichokes, chicory, asparagus, leeks, onions, garlic, and bananas. It is recommended we have at least 5 grams of prebiotic fibre a day, which would be hard to get from one source. So the more and wider variety of vegetables and fruit you can eat each day, the better.

So we know that prebiotics are needed to feed our beneficial bacteria, but what exactly is it that probiotics do? Probiotics are friendly bacteria that, when consumed, make it through the digestive tract to the large intestine where they help to increase the population and activity of the microbiome having a positive effect on health. The main types of friendly bacteria found in the gut are Lactobacillus and Bifidobacterium which play a crucial role in the gut’s ability to fight infection and support general digestion at the same time. Nowadays these friendly bacteria can be gotten from probiotic foods, probiotic drinks and probiotic supplements. The best way to benefit is to add natural probiotic foods to your diet.

Probiotic foods are more commonly known as fermented foods which have

seen a surge in popularity in recent years due to their proposed health benefits. Fermentation happens when friendly bacteria get to work on turning starches and sugars in foods such as milk, vegetables and fruits into lactic acid. The lactic acid acts as a preservative meaning that food then keeps for longer; it also helps to feed beneficial bacteria in your gut. A wide range of different friendly bacteria multiply during the fermentation process and so by regularly including fermented foods in your diet you are constantly nourishing your gut with a wide range of naturally occurring beneficial bacteria. Some fermented foods to include are:

  • Kefir – fermented milk drink with a creamy texture, sour taste and subtle effervescence made by adding a start culture called ‘kefir grains’ to milk. A dairy-free version of kefir also exists, called water kefir, which is a fermented beverage made of water, sugar and water kefir grains.

  • Kombucha - fermented tea beverage made from black/green tea, white sugar and a specific culture known as a scoby. Scoby stands for symbiotic culture of bacteria and yeasts.

– a form of preserved cabbage, common in countries like Germany and Poland, which is made from a combination of shredded cabbage and salt.

  • Kimchi – a group of salted and fermented vegetables, which originates from Korea. It consists of Chinese cabbage and/or radishes, and various flavouring ingredients (e.g., chili, pepper, garlic, onion, ginger), seasonings (e.g., salt, soybean sauce, sesame seed), and other additional foods (e.g., carrot, apple, pear, shrimps).

  • Others include fermented soy products such as natto, tempeh, miso; lassi, fermented vegetables and even sourdough bread.

By making a few tweaks and additions to your diet, you can easily support the health of your microbiome by including pre and probiotics, and hopefully reap the benefits.

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