Written by Marie Ellis
Reviewed by Sammie Gill
Poor gut health can cause a range of symptoms, and theses can affect your mental and physical health.
Luckily, there are many ways to support and improve your gut health.
For instance, some lifestyle changes, like eating more plants, sleeping well and staying active, can help.
Below, we explain what ‘gut health’ means. We also describe some signs of an unhealthy gut and what to do next.
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What is gut health?
Your gut, or gastrointestinal (GI) tract, digests your food, absorbs its nutrients and gets rid of waste.
The GI tract includes your mouth, oesophagus, stomach, small intestine, large intestine, rectum and anus.
‘Gut health’ isn’t a medical term. When people use it, they often mean the gut microbiome, which we’ll mostly focus on here.
What’s the gut microbiome?
The gut microbiome is the collection of microbes that live in your gut. This includes trillions of bacteria, viruses, fungi and other microbes.
Your large intestine is the last stretch of your intestines where poo forms. It’s home to your largest population of gut microbes.
Experts believe that a healthy gut microbiome supports good overall health. While they’re still figuring out exactly what makes a ‘healthy’ gut microbiome, they think it’s important to have a diverse range of microbes.
By the same measure, an unbalanced gut microbiome is linked to poorer health outcomes. This lack of balance is called dysbiosis.
One of the gut microbiome’s many jobs is helping you digest. In particular, it helps break down non-digestible nutrients (like fibre) and non-digestible compounds.
Some examples of these compounds are plant chemicals, like polyphenols.
Your gut microbiome can also produce vitamins, such as K and B vitamins, as well as hormones and neurotransmitters, like serotonin and dopamine.
As if these jobs weren’t impressive enough, the gut microbiome plays a key role in training your immune system, 70% of which sits along the gut.
When you eat high-fibre foods – like fruits, vegetables, whole grains and legumes – the fibre passes along until it reaches your large intestine.
There, your gut bacteria feast on the fibre, producing beneficial compounds as they work. These include short-chain fatty acids (SCFAs), which feed the cells that line your gut, helping to keep your gut healthy.
SCFAs also lower the gut’s pH level. This makes it harder for potentially harmful microbes to thrive.
A number of SCFAs enter your bloodstream and have positive effects on your whole body.
For example, studies in animals and humans have shown that SCFAs can help reduce cholesterol levels and regulate blood pressure.
Why is gut health important?
Research shows that some gut bacteria are linked to measures of good health, while others are linked to poorer measures. As a result, some gut bacteria are considered ‘good’ and others ‘bad.’
Scientists have found connections between dysbiosis – an imbalanced gut microbiome – and a number of health conditions, including:
- gut disorders, such as irritable bowel syndrome (IBS)
- gastrointestinal cancers, such as bowel cancer
- metabolic conditions, like type 2 diabetes and obesity
- cardiovascular conditions, including high blood pressure and high cholesterol
- immune-related conditions, including allergies and autoimmune diseases, like inflammatory bowel disease (IBD) and rheumatoid arthritis
There’s also growing evidence of links between the gut microbiome and brain health.
Signs of an unhealthy gut
Because your gut microbiome has such a wide influence on your health, an unhealthy gut can cause many symptoms, such as:
- GI symptoms: These can include diarrhoea, constipation, bloating and excess gas.
- Changes in weight: These might involve slow, unintentional weight loss or gain.
- Feeling tired: This might be due to sleep disturbances. Or, you might feel run down or have flu-like symptoms.
- Skin problems: Some evidence suggests that gut bacteria can influence skin health.
- Changes in mental health: This might include low mood or anxiety.
It’s important to mention that these symptoms can have many causes and may not relate to your gut microbiome.
If you’ve had any of these symptoms for a long period, speak with your doctor to find the cause.
8 ways to improve your gut health
Unlike your genes, which are fixed and passed down, your gut microbiome is not set in stone – it changes depending on how you treat it.
Did you know that we have many more microbial genes in our bodies than human genes? Genetically speaking, we are more than 99% microbial.
There are many ways to support this community of microbes. Here are some things you can do today to start improving your gut health:
1. Eat more plants
Your ‘good’ gut bacteria need fibre to survive. The best way to provide this fibre is by upping your plant intake.
Different microbes prefer different forms of fibre, so consuming a wide range of fruit and veg is a great way to boost your gut microbiome and increase its diversity.
Beyond fruit and veg, other high-fibre plants include:
- nuts
- seeds
- legumes, such as beans
- whole grains
2. Limit ultra-processed foods
In general, a whole-food approach is the best way to support your gut microbiome.
Ultra-processed foods, like snack bars, microwave meals and cakes and pastries, contain many additives.
These additives, such as emulsifiers, colours and stabilisers, might harm ‘good’ bacteria and encourage the growth of ‘bad’ bacteria.
Also, ultra-processed foods often contain high levels of salt, sugar and unhealthy fats, all of which can negatively affect the health of your gut and its microbiome.
3. Try fermented foods
There’s some evidence that eating more fermented foods – especially those containing live microbes – might help support your gut microbiome.
Some examples of these foods can include:
- natural or Greek-style yoghurt
- kimchi
- sauerkraut
- kombucha
When shopping, check the labels to make sure you’re getting a product with live bacteria.
Also, make sure to avoid ultra-processed versions. Flavoured yoghurts, for instance, often contain added sugar, colourings and emulsifiers. So, opt for a product with the fewest ingredients.
Some cheeses, like cheddar and Parmesan, also contain live bacteria.
4. Increase your polyphenols
Plants naturally produce compounds called polyphenols, which help protect them from infection and damage by sunlight.
When you eat plants containing polyphenols, they support the survival of ‘good’ bacteria in your gut.
That’s because, like fibre, around 90–95% of polyphenols are not digested in the small intestine.
Instead, polyphenols travel to the large intestine, where they’re fermented by gut microbes and release beneficial compounds.
Plants that contain high levels of polyphenols are often bitter, brightly coloured or both. Some examples of these plants (and the products we make from them) are:
- berries
- tea and coffee
- cocoa
- soy products
- spices
- beans
- nuts and seeds
- olives
5. Try probiotics
Probiotics are live microorganisms that can benefit your health. They’re available as pills, liquids and powders.
There’s evidence that taking certain probiotics can help increase the health and diversity of your gut microbiome.
6. Get enough sleep
The relationship between sleep and gut health seems to run both ways. Poor sleep is associated with a less healthy gut microbiome, while an unhealthy gut might impact your sleep quality.
Maintaining a regular sleep-wake cycle can help. Try to go to bed and wake up at around the same times every day, even on the weekends. And, if possible, get 7–8 hours of sleep each night.
But if you have trouble getting to sleep or staying asleep, speak with your doctor.
You can discover more ways to get better sleep in this article.
7. Manage stress
Research shows that stress may negatively affect your gut microbiome. The gut and brain are connected and constantly communicating with each other.
If you feel stressed, your gut will feel stressed too. This may have a negative effect on your gut microbiome.
We can’t always control our stress levels. But these techniques may help:
- doing yoga
- practising mindfulness
- getting enough sleep
- keeping active
- carving out some time for yourself
- getting a massage or trying self-massage
The relationship between stress and the microbiome may be another two-way street: stress may affect your gut microbes, and they may influence how you respond to stress.
8. Stay active
Among its many health benefits, exercise helps keep your gut in good shape. For instance, it reduces the risk of constipation.
Physical activity also promotes healthy blood flow to your organs, including the digestive system. This ensures that your body gets the energy and nutrients it needs to work well.
There’s even evidence that exercise might positively influence the makeup of your gut microbiome.
You don’t need to become a powerlifter or run ultra-marathons – anything to reduce the amount of time you’re sitting down can help.
You might start taking regular walks, going for a swim at your local leisure centre, or trying a dance class or an online workout.
Summary
The health of your gut and its microbiome can affect the health of your whole body.
An imbalance in your gut microbiome (called dysbiosis) is linked to conditions like IBS and diabetes, as well as mental health conditions.
Some signs of an unhealthy gut include digestive problems and changes in your weight or mood.
Thankfully, there are things you can do today to improve your gut health.
For instance, eating fiber- and polyphenol-rich foods, trying fermented products and probiotics, getting enough sleep, staying active and managing your stress can all help.
To learn more about bloating and other gut health topics, visit Symprove’s Gut Hub.
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