How to improve your gut health and why it matters

‘Gut health’ has become a popular term. But unlike many fads, the importance of gut health is backed by scientific evidence. 

Here, we’ll explain why gut health is vital and how you can support yours with simple diet and lifestyle changes. 

There’s no agreement among experts about what 'gut health' means. But the term often refers to the functioning of the entire gut, all 8–9 metres from top to bottom.

In recent years, a key focus has been the gut microbiome. So, in this article, we’ll look at the workings of the gut and highlight its collection of microbes. 

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What's the gut microbiome?

Although scientists have known about the gut microbiome for more than a century, they’re only beginning to understand its complexity and importance for overall health.

Experts already know that the gut microbiome plays a fundamental role in the health of many organs, including the brain and heart.

Your gut microbiome is a collection of trillions of microorganisms that live in your gut. In particular, your colon – or large intestine – is a hotspot for microbes, including:

• bacteria
• viruses
• protozoa
• fungi
• archaea

All of these microorganisms are likely important, but so far, scientists have mostly focused on bacteria.

Some species of bacteria are linked to better health, such as more favourable blood sugar responses and better cholesterol levels. For example, species of Lactobacillus and Bifidobacterium bacteria have been widely acknowledged for their health-promoting characteristics. 

More recently, Faecalibacterium prausnitzii and Akkermansia muciniphila have become well-known for their anti-inflammatory effects. 

Meanwhile, other species of bacteria may not be so good for us. 

In general, scientists believe that having a diverse range of ‘good’ bacteria is a sign of a healthy gut microbiome. Having lots of ‘bad’ bacteria or low diversity is called dysbiosis.

Looking beyond diversity, what makes a microbiome ‘healthy’ is its stability and resilience. 

The human body contains around 20,000 genes, which you inherit from your parents. But everyone (except identical twins) has a unique set of genes. 

What’s interesting is that even identical twins have different microbiomes – each one is unique. 

The gut microbiome contains around 2 million genes. So, you could say that your body is more than 99% microbial.

You can’t change your DNA, but you do have the power to change the microbes in your gut. There are many ways to support and improve your gut microbiome, and we’ll explain how later on.

The gut microbiome and health

It may be surprising that organisms in your gut can influence your overall health. Just as good food can nourish your whole body, these microorganisms have wide-reaching effects. But how?

Gut bacteria look after us in a number of ways. For instance, as these bacteria break down and ferment fibre in your gut, they produce new compounds, such as short-chain fatty acids (SCFAs).

SCFAs provide the primary fuel that powers the cells lining your gut. 

Some SCFAs even make it to your brain and may help reduce appetite and play a role in maintaining a healthy weight.

SCFAs may also help your gut absorb more nutrients, such as calcium, magnesium and iron. 

Meanwhile, some gut microbes can produce neurotransmitters, such as serotonin, dopamine and γ-aminobutyric acid (GABA). These chemicals play key roles in brain health.

Other gut microbes can alter levels of hormones, such as oestrogen.

So, we’ve seen that gut bacteria release helpful compounds. They also help support your immune system.

The interaction between microbes and immune cells in the gut helps ‘train’ your immune system, making sure it responds appropriately to threats. 

At the same time, scientists have identified links between the gut microbiome and a wide range of conditions, including:

• digestive diseases, like inflammatory bowel disease (IBD)
• autoimmune conditions, such as coeliac disease, rheumatoid arthritis and type 1 diabetes
• neurodegenerative diseases, including Alzheimer’s and Parkinson’s diseases
• metabolic conditions, such as type 2 diabetes and obesity

Important note: Scientists don't know whether changes in the gut microbiome directly cause a health condition or whether the health condition causes changes in the gut microbiome. It's probably a bit of both.

But we do know that certain gut microbes or other aspects of the gut microbiome – like species diversity – are associated with health conditions. 

For example, people with IBD often have lower levels of Faecalibacterium prausnitzii. 

6 signs of gut health 

There’s no single best way to measure gut health. But answering these questions can provide a clearer understanding of your own situation. 

1. How often do you poo?

There’s a great deal of variation, but if you poo between three times a day and three times a week, experts consider it healthy. This is called the 3 in 3 rule.

If you’re outside of that range, it might be a sign that something’s up.

2. What’s your poo like?

Besides how regular you are, the shape, colour and consistency of your poo can give you clues about your gut health.

Signs of a healthy gut:

• firm, sausage-shaped poo
• poo with a smooth texture
• poo that sinks in the toilet 
• poo that leaves your bum in one large or just a few smaller pieces

Signs of an unhealthy gut:

• lumpy or hard poo – often a sign of constipation
• liquid or very soft poo – also called diarrhoea
• floating poo – this may contain undigested fat

As for colour, your poo should be medium to dark brown. But sometimes the colour can vary for a little while, especially if you've eaten lots of dark, leafy greens or beetroot.

Some medications and supplements (like bismuth-based drugs or iron tablets) can also change the colour of your poo. 

In other cases, certain colours can point to gut health issues.

If you haven’t eaten anything brightly coloured, like dyed foods, beetroot or lots of leafy greens:

• Green poo can signal a gut infection or bile acid diarrhoea. 
• Black poo can result from iron supplements or bleeding higher up in your intestinal tract.
• Red or reddish poo might result from bleeding lower in the tract, haemorrhoids or a gut condition, such as IBD.
• Yellow poo is sometimes caused by undigested fat or an infection.
• Greyish poo might stem from a lack of bile, a fluid that helps you digest fat.

If you’re worried about the colour of your poo, talk with your doctor.

3. Painless poos

If you have to strain to push out poo, you might be constipated. There shouldn’t be any discomfort, and poo should come out easily.

If you experience pain when you poo, it might indicate a health condition, like irritable bowel syndrome (IBS), constipation, haemorrhoids, IBD or proctitis. So, it’s important to speak with your doctor.

4. Wind and bloating

It’s natural to experience wind and occasional bloating. But if you have bloating or pass a lot of gas often, it might show that your gut needs some love.

If you regularly experience bloating, we have an article outlining 10 ways to reduce bloating. 

We also have one specifically for females who feel bloated, sick and tired and another on foods that can help reduce bloating.

However, if the issue continues, make sure to visit your doctor. 

5. Heartburn and acid reflux

The painful sensation of heartburn happens when the acidic contents of your stomach flow back up into your oesophagus (food pipe). This journey is called acid reflux.

Most of us have heartburn at some point in our lives. But if you experience it very regularly, it might be gastro-oesophageal reflux disease, also called GORD.

If this sounds familiar, speak with your doctor, who can suggest treatments and strategies.

6. Fatigue and colds 

If you’re very often tired and susceptible to colds, it could relate to your gut health.

About 70% of your immune system is located along your gut, and your immune system is in constant communication with your gut microbiome.

Scientists have found connections between the gut microbiome and our susceptibility to respiratory infections, including the flu. 

5 dietary changes to improve gut health

We’ll now describe some changes to your diet that can support the health of your gut and the microbes that call it home.

1. Fibre, fibre, fibre

As we’ve mentioned, gut bacteria feed on the fibre in your diet.

Fibre also helps keep you regular and can improve diarrhoea and constipation. So, it’s important to eat fibre-rich foods regularly. 

The best sources of fibre are plants: fruits, vegetables, nuts, seeds, legumes, whole grains, herbs and spices.

Variety is key – different microbes have different ‘preferences’, so eating as many different plants as you can helps ensure that your microbes are getting what they need.

Small changes towards diversity in your diet can make a big difference.

Guidelines suggest that we should all eat around 30 grams of fibre per day, but on average in the United Kingdom, we eat just 18 g. This means that most people would benefit from upping their intake.

Foods that are particularly rich in fibre include:

• fruits, such as berries, apples, and pears – with the skin on
• vegetables, such as broccoli, cauliflower, peas, sweetcorn and carrots
• whole grains, such as rye and oats
• legumes, such as chickpeas, lentils and beans
• nuts and seeds

If you’d like more inspiration, try this article on high-fibre breakfasts. We also have a handy meal plan to help you reach 30 g of fibre per day.

Fibre supplements are also available – psyllium husk is one example. While these supplements can help in certain scenarios, it’s better to consume fibre in whole foods.

Different gut bacteria prefer different types of fibre, and supplements tend to contain only one form. And, unlike fibre supplements, whole plants are abundant with vitamins, minerals and beneficial compounds such as polyphenols.

Important note: Because many of us don’t eat enough fibre, it’s a good idea to up your intake slowly to give your gut time to adjust.

2. Probiotics

Probiotics are specific types of live bacteria. When you consume them, they can support your gut health and reduce symptoms of certain gut conditions, like IBS. 

You can learn more about probiotics in this article, and find details about probiotics and bloating here. 

3. Fermented foods

Humans have enjoyed fermented foods for thousands of years. 

Earlier in our history, we fermented food so it would stay edible longer. Today, scientists are discovering that these foods have gut health benefits.

Bacteria drive the process of fermentation. As they do this, they create many new compounds that might support our health.

And some fermented foods contain bacteria that help support your gut microbiome.

Some delicious fermented foods to try include:

• sauerkraut
• kimchi
• kombucha
• natural or Greek yoghurt
• some cheeses

For more information, including how to choose the best options, read this article on fermented foods.

4. Eat the rainbow

This phrase has become popular for good reason. By eating differently coloured fruits and vegetables, you increase the diversity of plants in your diet.

As we’ve mentioned, this strategy helps your gut bacteria, giving them a range of fibre types to consume.

Also, brightly coloured fruits and veggies tend to have more polyphenols. These are defence chemicals that protect the plant from sunlight and predators. 

It’s good for us to consume polyphenols because they have anti-inflammatory and antioxidant properties. 

They also help feed your ‘good’ gut bacteria. In fact, around 90–95% of polyphenols reach the large intestine and are fermented by gut microbes.

5. Cut back on ultra-processed foods

High-fibre and fermented foods can support your gut microbiome and your overall gut health, but certain foods might do the opposite.

For instance, ultra-processed foods (UPFs) are often low in fibre but high in sugar, unhealthy fats and salt. These foods can disrupt your community of ‘good’ gut bacteria and encourage the growth of ‘bad’ ones. 

Examples of UPFs include cakes, biscuits, pastries, pies, takeaways, fast food, crisps and hot dogs. 

Similarly, there’s evidence that certain food additives in UPFs, like some emulsifiers, might be bad news for your gut bacteria. 

Researchers are still tracing the precise links between UPFs and the gut microbiome, but there’s strong evidence that a high intake of UPFs is linked to poorer health.

It’s almost impossible to avoid UPFs entirely, but it’s good to reduce your intake whenever you can.

Learn more about UPFs here.

5 lifestyle changes to improve your gut health

Tweaking your diet isn’t the only important way to look after your gut. The following lifestyle changes can also help.

1. Keep active

Exercise is great for every aspect of our health, including our gut health. Moving around helps food travel through your gut, and it keeps you regular. 

Surprisingly, scientists have also found links between physical activity and a healthy gut microbiome.

But you don’t need to train for a marathon; just walking can have benefits. For instance, research shows that regularly taking a walk and practising yoga are each linked to reduced symptoms of IBS.

Also, exercise can help you lose excess weight, which can help reduce symptoms of heartburn for some people. 

2. Get good sleep

The links between sleep and gut health may surprise you.

Some research suggests that getting better sleep is associated with a more diverse gut microbiome.

Scientists are still investigating the relationship, but it seems to be a two-way street: Your gut microbiome can influence your sleep quality, and your sleep quality can influence your gut microbiome.

In general, try to go to bed and wake up at the same times, even at weekends. And aim to get 6–8 hours of sleep each night.

Here are more tips for quality sleep:

• Keep your room cool and dark.
• Don’t lie in bed for a long time before you go to sleep.
• Avoid alcohol close to bedtime.
• Don’t eat in the 2–3 hours before bed.
• Avoid caffeine after lunch if you’re especially susceptible to it.
• Try not to use screens just before bed: turn off notifications or set your phone to silent.

3. Reduce your stress levels

It’s impossible to avoid stress entirely. But taking steps to reduce it when you can might benefit your gut health. 

Research shows that stress can make symptoms of gut conditions worse. And if stress continues long-term, it can increase the risk of developing new gut problems.

If you’re often stressed, these approaches may help:

• yoga
• physical exercise
• meditation
• talking therapy
• cutting back on social engagements

It’s also a good strategy to make time for yourself. Set aside time to read a book or take a warm bath, maybe with some candles or that CD of panpipe cover versions that’s gathering dust on your shelf.

4. Eat more slowly

If you eat quickly, the likelihood of heartburn and indigestion increases.

Research also shows that people who eat more quickly are more likely to consume more energy and have a higher body mass index (BMI).

So, if you’re a fast eater, here are some tips:

• Put away your phone or laptop and focus on each mouthful.
• Rather than eating on the move, make sure to sit comfortably.
• Put down your knife and fork between mouthfuls.
• Take a sip of water between mouthfuls.
• If you’re with a slow eater, follow their lead.
• Aim for 10–20 chews per mouthful.
• Don’t wait until you’re famished before you have a snack or meal.

5. Stop smoking and limit alcohol 

Quitting tobacco and cutting down on alcohol are smart moves for many reasons, including benefits for your gut health.

Smoking increases the risk of acid reflux, and both smoking and drinking alcohol can disturb your gut microbiome.

Summary

Good gut health can support good general health. 

How often you poo (and what pooing looks and feels like) can provide insights about your gut. Discomfort, bloating and excess wind can signal that your gut needs support, as can frequent tiredness, colds and generally feeling unwell.

Often, when people say ‘gut health’, they’re referring to a thriving, diverse gut microbiome. The great news is that there are many ways to improve your gut microbiome and overall gut health. 

Helpful strategies include reducing stress, sleeping well, staying active, trying probiotics, and reducing your intake of alcohol, ultra-processed foods and tobacco. 

Eating more fibre, fermented foods and colourful plants is also a great idea. If you look after your gut, your gut will look after you.

To learn more about gut health and other topics, visit Symprove’s Gut Hub.

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