Dysbiosis (pronounced dis-by-osis) is a change from the healthy or normal makeup of your microbiome – the trillions of microbes that live in and on you.
The human body actually has many microbiomes. Dysbiosis might be affecting the skin or vaginal microbiome, but people generally use the term to refer to the gut microbiome.
One big question that scientists are trying to answer is whether dysbiosis is the cause or effect of a health condition. In other words: Is a health condition triggering dysbiosis or is dysbiosis triggering a health condition?
Common factors that are thought to cause dysbiosis include stress, an unhealthy diet, alcohol consumption, infections and antibiotics.
When dysbiosis happens, it can disrupt the relationships between microbes and might increase the risk of illness.
In this article, we’ll explain more about dysbiosis, including why it happens, what it might feel like and how you can prevent it.
What is dysbiosis?
Your body is home to trillions of microbes, including bacteria, fungi, viruses and others. The vast majority of these microorganisms aren’t bad for you, and many can actively support your health.
They live on your skin, in your mouth and even in your lungs. The largest population, however, is in your gut, and most of these microbes are in your large intestine.
Your microbes live in close quarters and develop working relationships with each other. Some species support one another, while others inhibit the growth of ‘bad’ bacteria.
Like any ecosystem, your microbiome relies upon relationships – your microbes working in harmony and maintaining balance.
However, if this delicate balance is disturbed, it can cause issues. Here’s a quick analogy: Imagine a forest with an abundance of animals and plants. Because of the balance of species, there’s food and space for all.
If, one day, a huge herd of hungry deer turned up, they would strip the forest of its plants. With fewer plants, smaller mammals and birds might not find enough to eat and would die off. At the same time, predators would have a feast, increasing their numbers.
Similarly, an influx of one type of bacteria, or a lack of another, can cause an imbalance in your gut microbiome that affects how it works.
Experts sometimes split dysbiosis into three types:
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a loss of ‘good’ gut bacteria
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an overgrowth of ‘bad’ gut bacteria
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a loss of overall diversity of gut bacteria
Often, all three occur at the same time.
It’s important to note that this area of research is still relatively new, and not all scientists agree on the definition of dysbiosis.
Why are gut bacteria important?
Gut bacteria help you digest your food. And as research has advanced over the last few decades, it’s become clear that gut bacteria’s beneficial effects are also felt much further afield. That’s why, when dysbiosis occurs, it can affect you in many different ways.
For the rest of this article, we’ll mostly focus on gut dysbiosis, which scientists have spent the most time investigating.
Gut dysbiosis: Symptoms and health conditions
More and more research now suggests that dysbiosis may be a factor in the development of health conditions. But it’s important to remember that health conditions are often complex and can involve many factors, including your genes, environment and lifestyle.
Naturally, with so much focus on the gut, there’s been a lot of interest in gut-related conditions, such as:
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gut infections
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irritable bowel syndrome (IBS)
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inflammatory bowel disease (IBD)
You can learn about the difference between IBS and IBD here.
Common symptoms typically linked with dysbiosis include pain, bloating and diarrhoea.
Beyond the gut, other health conditions have also been associated with dysbiosis, including:
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immune-mediated and autoimmune conditions, like type 1 diabetes, lupus and rheumatoid arthritis
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metabolic conditions, including type 2 diabetes, atherosclerosis and high blood pressure
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colorectal cancer
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neurological conditions, like Parkinson's disease
The gut microbiome is linked to the brain through a network of relationships called the gut-brain axis. For this reason, dysbiosis may also play a part in mental health conditions and chronic fatigue.
What causes dysbiosis?
Several factors can cause or increase the risk of developing dysbiosis, including your:
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Genetic background: Some people may be more susceptible than others.
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Health status: Infections and inflammation, for example, can increase the risk.
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Lifestyle factors: This includes smoking tobacco and excess alcohol consumption.
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Diet: A high intake of refined sugar or a low intake of fibre can each increase the risk of dysbiosis. Also, certain food additives, like emulsifiers and artificial sweeteners, may play a role.
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Some medications: For instance, antibiotics can cause dysbiosis because they often kill a wide range of bacteria, not just the ‘bad’ ones responsible for an infection.
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Psychological stress: There’s evidence that long-term stress can disrupt the healthy balance of microbes in your gut.
How is gut dysbiosis diagnosed?
At the moment, it’s not possible to diagnose gut dysbiosis.
Clinical tests have very clear cut-off points, indicating what’s healthy and what’s not. But there’s no universally accepted benchmark for what’s considered a healthy microbiome and what might indicate dysbiosis.
Gut microbiome testing has surged in popularity over the last few years. These tests will tell you the type and amounts of bacteria in your gut and whether those bacteria are common in thousands of other people.
What these tests can't tell you is whether the bacteria in your sample are healthy or unhealthy for you.
That’s because your gut microbiome is unique to you – a bit like a fingerprint.
Also, a gut microbiome test shows you one 'snapshot' in time. This is important to remember because the gut microbiome fluctuates daily.
What to do about gut dysbiosis
It’s best to work with your doctor or dietitian to figure out the best course of action to address any gut-related issues you’re experiencing.
They will advise you about the best treatment options based on the cause.
For instance, if an infection is causing your symptoms, your doctor may prescribe antibiotics. Conversely, if the cause is antibiotics, they may change the type of antibiotic that you’re taking.
Other treatments might involve:
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Taking probiotics: These live, ‘good’ bacteria can help restore the balance of your microbiome.
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Dietary changes: This may involve upping your intake of fibre-rich foods, like fruits and vegetables, and reducing your intake of refined sugars.
More broadly, looking after your gut microbiome can have many other health benefits.
Lifestyle strategies to support your gut microbes include:
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eating a plant-based diet
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minimising stress
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keeping active
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spending time outside in green spaces
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not smoking or drinking alcohol in excess
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maintaining a consistent sleep pattern
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only taking antibiotics when required
FAQs
In this section, we’ll answer some frequently asked questions about dysbiosis.
What are the signs and symptoms of dysbiosis?
The signs and symptoms of dysbiosis vary depending on where the imbalance occurs.
For instance, dysbiosis of the skin microbiome might cause redness or rashes, whereas gut microbiome dysbiosis may cause bloating, stomach pain and diarrhoea.
How do you fix gut dysbiosis?
The best treatment depends on the cause. For example, a gut infection might require a course of antibiotics.
Speak with your doctor or dietitian if you have symptoms such as pain, bloating and changes to your bowel habits, as these may indicate dysbiosis.
Which foods cause dysbiosis?
Consuming large quantities of certain foods and drinks may be linked to an increased risk of gut microbiome dysbiosis.
The foods tend to be high in refined sugars and low in fibre. Some examples include:
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takeaways and fast food
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cakes, pastries, chocolate, biscuits and crisps
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processed meats, such as ham and sausages
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alcohol
On the other hand, plant-based foods rich in fibre and plant chemicals may help reduce dysbiosis.
How long does it take for gut dysbiosis to heal?
The time it takes to restore balance to your gut microbiome depends on a number of factors, including how severe the dysbiosis is and what caused it.
For instance, if dysbiosis results from antibiotics, your gut microbiome will begin to recover naturally once the course of antibiotics is finished.
Thankfully, your gut microbiome is incredibly resilient, so by feeding it the right foods, you can make changes within just a few days.
Summary
Dysbiosis is an imbalance of microorganisms in one of your body’s microbiomes.
Gut microbiome dysbiosis is associated with a wide range of health conditions, including short-term issues, like infections, and long-term conditions, like IBD.
Dysbiosis may also play a role in other illnesses, such as type 2 diabetes and conditions affecting your immune system or mental health.
Currently, no test can diagnose gut dysbiosis. Still, it’s important to speak with your doctor if you’re concerned about your gut health.
Strategies to maintain a healthy, balanced gut microbiome include eating a plant-based diet, minimising stress and keeping active.
There’s also evidence that spending time outdoors in green spaces, not smoking or drinking in excess, and maintaining a consistent sleep pattern can help.
To learn more about other gut health topics, visit Symprove’s Gut Hub.
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