By Will Hawkins

The benefits of gut bacteria: Exploring our second brain

We often get mixed messages when it comes to bacteria. But when it comes to our gut, we need to start thinking of bacteria as a friend, not an enemy!

Why? Well, here's some of the science behind it:

Our gut microbiome is a population of microbes including fungi, bacteria & viruses - that live in our body. And there are trillions of them! This includes lots of different species of bacteria, which mostly sit within our small intestine and colon.

What was once 'the forgotten organ', our gut and its microbiome have boosted their profiles within the medical and health communities in recent years, with some referring to the gut as the 'second brain of the body'.

Professor Siobhan Norton said: The gut is more than just a mulching factory for food, it is the second brain of our body, almost as important as the brain itself.

With our knowledge about our guts advancing so quickly,, doctors can now advise on not only our diets, but our overall health with gut bacteria in mind.

Gut bacteria - the good, the bad and the science

Our gut is responsible for performing vital functions that allow us to maintain our health, through the balance of different types of bacteria: our 'good' and 'bad' bacteria.

What's good bacteria, and what's bad bacteria?

Bad bacteria can make its way to our gut through the food we eat, the air we breathe and the water we consume. This is the bacteria that causes us to become unwell, and usually requires antibiotics to fight off.

Good bacteria settles within our body too though, providing us with essential nutrients and protecting us from infections, rather than causing them. However, when your 'good' gut bacteria and 'bad' gut bacteria become imbalanced, and changes in our gut can cause some unpleasant side effects:

With so many symptoms arising from an unhealthy gut, it's easy to see how an imbalanced microbiome may be linked to other, long-term illnesses.

A wonder cure? Your gut and your health

With the wide range of health problems arising from upset guts, it's no surprise that doctors around the world are considering gut health in patients' treatment plans.

Doctors, neurologists and psychiatrists are all looking at gut-focused treatments for a range of conditions that were previously thought not to be related. Even critical-care specialists, who work in intensive care, are getting involved in how we can implement strategies around gut health for some of the sickest patients.

This is because a well-balanced gut microbiome is thought to:

  • Protect us from infections
  • Support all mental functions gut bacteria have been linked to the production of chemicals in the brain, including serotonin which acts as the body's natural antidepressant.
  • Regulate blood sugar
  • Impact body composition
  • Improve heart health by reducing cholesterol
  • Strengthen our immune system

And you only need to look into the stats around some of the UK's biggest health problems to realise the impact these benefits could have on the nation:

  • 86% of British adults suffered from a gastrointestinal problem from 2016-2017
  • 1 in 16 people have diabetes
  • 1 in 4 people experience mental-health related symptoms
  • An estimated 7 million people in the UK live with cardiovascular disease

So, how can we start taking action and improving our health using bacteria?

Food for thought - what to eat for good gut health

Even though we see TV ads for digestive health yogurts daily, I see the popularity of these foods and nutrients as more than just a fad. I see them as a return to the traditional, natural ways of eating that our ancestors developed. There's evidence that countries incorporate this kind of thinking into their diets all over the world.

For example, pickled ginger with sushi and miso broths are popular traditional Japanese dishes. In India, fermented foods like a yogurt-based drink called Lassi are often dietary staples. Kimchi is big in Korea, as is kefir in the Middle East. Are you seeing a trend here?

These are all gut-friendly additions to diets all over the world and it's no coincidence that they're good for us. By returning to our nutritional roots, we can all add some bacteria-heavy foods into our diets and start working towards a healthy gut.

Prebiotic foods

Whilst most of us have heard about probiotics, prebiotics are specialised types of fibre that are indigestible by the human intestine, but our microbes are able to break them down.

Prebiotics fibres feed our microbes and keep them healthy! And luckily, there are loads of fibre-rich foods your gut bugs and taste buds will love.

The beneficial bacteria feeding off these prebiotic-rich foods have been found to have anti-inflammatory effects on our digestive system and improve our immune system, making these ingredients a must-have on your next shopping list.

Prebiotics-rich foods include:

  • Artichoke
  • Garlic
  • Onions
  • Leeks
  • Asparagus
  • Bananas
  • Oats
  • Apples
  • Flaxseeds
  • Cocoa

Probiotic foods

Despite the popularity of probiotic supplements and powders, it's important to note not all these products are created equal, and they should only be used to supplement a healthy well-balanced diet, not replace it.

A lot of fermented foods have high levels of good bacteria, as they are grown during the fermentation process. This means foods like yogurts and sauerkraut (fermented cabbage) help your digestive health, whilst also being linked to weight loss and a healthy heart.

Foods that are a good source of probiotics include:

  • Greek yogurt
  • Kefir
  • Sauerkraut
  • Dark chocolate
  • Miso soup
  • Pickles
  • Kimchi
  • Yakult

Some studies have shown probiotic foods have an anti inflammatory effect on the body, helping with urinary tract disorders and irritable bowel ;syndrome.

I'd encourage experimenting with different ingredients such as probiotic yogurts or kimchi that are full of different strains of beneficial bacteria. All are usually found in the refrigerated section of the supermarket, and easy to get hold of.

Polyphenol-rich foods

Polyphenols are chemicals we find in plants - of which there are literally thousands! Consuming a healthy amount of polyphenol-rich foods has been linked with improved gut lining as well as encouraging the growth of microbes.

The good news is that a diet full of the foods below (and even a small glass of red wine, every so often!) can also reduce your risk of heart disease,

Foods high in polyphenols include:

  • Cocoa powder
  • Dark, leafy vegetables
  • Beetroot
  • Green tea
  • Berries
  • Tomatoes


Spices can have an unbelievable effect on our body.

Spices good for your gut bacteria include:

  • Tumeric
  • Chilli
  • Cumin
  • Cinnamon
  • Paprika

These popular spices have all been found to have a proven effect on reducing inflammation in the gut.

Reducing inflammation allows for greater cultivation of bacteria, leading to a healthy gut.

A varied diet equals a healthy digestive tract

Your gut bugs favour diversity. They thrive on new, interesting foods which may encourage you to try new foods as much as possible!

Studies suggest that there appears to be an improvement in the range of gut bacteria populations when a variety of foods are consumed.

Exercising caution with refined carbohydrates, sugars and sweeteners

Refined carbohydrates, sugars and sweeteners all things that we most likely regularly consume, and all which can have a negative effect on our gut microbiome.

'Diet' versions of popular drinks and foods with synthetic sweeteners aren't bad in moderation, but excessive amounts have been shown to have a detrimental effect on your overall health and your microbiome.