What is the microbiome?

Everything you need to know about the microbiome, from what it is to why it’s so exciting.

The microbiome has been everywhere recently—it’s one of the most exciting areas of health research, and we now know it plays a central role in your overall health, not just your digestive function. But there’s a lot of confusing information out there. On the one hand, you have scientific papers, which while important, aren’t known for being easy reads, and on the other, you’ve got buzzwords and unscientific claims . We want to change all that.

In this article, we’ll look at what the microbiome actually is, how it impacts your health, and what you can do to look after it.

What is the microbiome?

Your body contains trillions of microorganisms—bacteria, viruses, fungi, and more—living together symbiotically, all benefitting from each other’s presence, and of course, you. Together, these microorganisms make up your microbiome. It’s like an entire universe, entirely inside you.

Technically, you can talk about multiple microbiomes around your body, the two largest being the skin and the gut, but we’re going to focus on the gut microbiome. It’s the biggest, and it touches upon almost every aspect of your health.

While some microorganisms, such as E. coli or norovirus, are associated with disease, these only make up a tiny proportion. For example, there are estimated to be fewer than 100 pathogenic species of bacteria, while several thousand species of bacteria live in your gut. The vast majority of these are vitally important for your gut, mental health , immunity, and many other aspects of your overall health. That’s what makes your gut microbiome one of the powerhouses of the body, and such an important system to take care of.

What does the microbiome do?

So that’s the microbiome. But what exactly does it do? How is it that a collection of bacteria living in your colon can have such a profound impact on how we feel and how we function?

It promotes better digestion

A microbiome with lots of diverse bacteria produces thousands of chemicals known as metabolites, three of the most important of which are butyrate, acetate, and propionate. These metabolites help support your digestive function and reduce occasional gastrointestinal discomfort, like bloating, gas, or constipation.

On top of that, a healthy microbiome with good diversity can help reduce proteolytic fermentation. This is when certain bacteria ferment protein and release harmful chemicals such as ammonia, amines, phenols, and sulphides. These are what cause farts to smell, and proteolytic fermentation is one of the reasons that diets excessively high in meat with inadequate fruits and vegetables cause foul-smelling gas and stools, and have unfavourable health outcomes.

It aids the immune system

70% of your immune system is in your digestive tract. As well as the obvious physical barriers—such as your stomach acid, which kills most bacteria it comes into contact with— your microbiome itself is essential in the development and maintenance of your immune system.

The microorganisms in your gut work with activated B cells, which produce antibodies using information provided by your microbiome. This helps develop a huge immune knowledge bank, so your body is ready to fight off illness.

On top of that, the microbiome also has a crucial role to play in the modulation of our immune function—it supports us in switching on or switching off our immune system, responding to various microbial and other threats in the body. This helps to prevent things like autoimmune reactions, which are becoming more common in modern living.

It supports mental health

Our gut bacteria also help to support our mental health by producing a large proportion of certain neurotransmitters, such as serotonin and dopamine, which maintain a good balance of happy chemicals in the brain. For example, the bacteria in the gut produce 95% of the serotonin in your body.

Through the gut-brain axis , the microorganisms in your gut can also create feedback loops in the hypothalamic-pituitary-adrenal connection (a key hormonal network), regulating cortisol (stress hormone) production. An imbalanced microbiome is also associated with many diseases and mood disorders. By focusing on strengthening and feeding your microbiome, you can restore normal microbial balance, which may potentially have a role in regulating your mental health.

And that’s not all

The microbiome is often linked with the three areas above, but it impacts so much more than those. From cardiovascular health to skin blemishes, from bone density to eyesight, it all comes back to your gut microbiome.

How else does your microbiome affect you?

It’s important to stay on top of the health of your microbiome, and be able to recognise when you need to give your gut a little bit of extra care and attention. Prolonged gastrointestinal discomfort is an obvious sign, but there are many others that you wouldn’t necessarily associate with the gut.

Discover five ways your gut might be telling you it needs a little bit of love .

6 ways to look after your microbiome

Once you decide that you want to put a bit more time and thought into taking care of your gut microbiome, it can still be hard to know where to start. There’s a lot of competing information on the internet, but we’ve broken it down into six simple things you can start right now.

1. Eat a diverse range of foods

The more diverse the diet , the more diverse the microbiome, a key indicator of good gut health. In particular aim for foods that are high in prebiotic fibre. These indigestible fibres are found in vegetables like artichokes and leeks, and are an excellent source of nutrition for your gut bacteria.

2. Eat plenty of fermented food

Fermented food on its own is unlikely to deliver much live bacteria to the gut, as your stomach acid does a very good job of killing off any microorganisms it comes into contact with. However, probiotic-rich foods like kimchi, sauerkraut, and kombucha are still able to get some bacteria to your colon, and studies show a correlation between eating these foods and having a good microbial diversity.

3. Take a probiotic supplement

A high-quality probiotic supplement can deliver live bacteria to the colon more effectively than probiotic-rich foods, thanks to delayed-release technology and acid-resistant strains. Research suggests that supplementation can help increase microbial diversity in the gut, which is linked to overall physical and mental health.

4. Avoid too much sugar

Don’t go overboard—an overly restrictive diet is never a good idea unless you’ve been advised by a healthcare professional. But some studies suggest that a diet high in refined sugar is linked to a gut microbiome that encourages inflammation, so it’s probably best to avoid enormous amounts of refined sugar.

5. Get moving

Exercise isn’t just good for your brain and body, it’s also good for your gut. Evidence suggests that exercise can enhance the number of beneficial microbial species, enrich the microflora diversity, and improve the development of your gut bacteria, all of which lead to a stronger microbiome, and potential health benefits.

6. Have a nap

Even sleeping can have an impact on your microbiome. This is an example of the gut-brain axis working the other way. If you aren’t getting enough sleep, you’re more prone to feeling stressed in everyday situations. This response may have an adverse impact on the diversity of your microbiome.

None of these are miracle answers to microbiome health, but together, they can help support your gut bacteria, and help them thrive. Because if one thing’s clear, it’s the importance of the microbiome when it comes to your overall health, from what you’d expect—digestion—to what you wouldn’t—mood. So if you want to stay healthy and experience the benefits of good gut health, long-term, start thinking about what you can do to maintain a strong, healthy microbiome.

Your gut microbiome is one of the most important systems in your body, and it’s in constant communication with your brain. Discover more about the gut-brain axis now.


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