What Are The Symptoms Of An Unhealthy Gut?

One in five people in the UK have been diagnosed with IBS [Source: NHS]. That means twenty percent of us are living with life-limiting symptoms like diarrhoea, constipation, pain and bloating.

That’s just the tip of the iceberg.

Many more people have those symptoms and haven’t been diagnosed with IBS. And many more still suffer with conditions that may not give them bowel symptoms, but are connected with poor gut health.

Read on to find out more about the many health conditions with links to an unhealthy gut.

Symptom #1: Bloating

Bloating can happen for a number of reasons. If your bloating is severe, tell your doctor. There are some serious conditions that could be causing it, like ovarian cancer or liver disease. However these are very rare, so please don’t panic. It’s just best to get it checked out.

The usual reason you get a bloated belly is because your gut microbes are eating what you’ve just eaten [Source: PubMed]. When they do that, they release gases that stretch your gut walls, a bit like blowing up a balloon. While the microbes in a healthy gut also release gases, they don’t produce excess amounts that make you uncomfortable.

Another reason is that the gas is trapped: it’s not moving along your intestines as it should, so it builds up [Source: PubMed]. So, rather than a problem with too much gas, it’s a problem with what we call motility (the natural movement of your gut).

Discover the cause for your symptoms.

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Remedies for the symptoms of bloating

There’s a reason that your gut microbes are having a party and producing too much gas, and that reason is often dysbiosis [Source: PubMed]. That means that the communities of microbes in your gut are imbalanced. 

We all have around 1000 species of bacteria and other microbes down there, and ideally, they should all be living in harmony. But with our modern diets and lifestyles, that’s becoming increasingly rare.

To tackle bloating for good, you need to find the root cause. Root causes of bloating can include:

  • SIBO
  • Candida overgrowth
  • Parasite infection
  • An overgrowth of less friendly bacteria

All of these are types of dysbiosis.

We have an accurate, at-home SIBO test you can order today. Find out more about SIBO testing on our blog How do you get tested for SIBO?

Of course, you may want to be rid of your bloating here and now, while you dig into your possible root causes. To relieve bloating fast, try:

  • A low-FODMAP diet [Source: PubMed]
  • Bitters’ before you eat: they activate receptors on your tongue that signal the production of more digestive juices further down in your digestive tract. Dandelion, gentian root, burdock, yellow dock, and Angelica are examples of bitter herbs.
  • Diuretic foods: they help with digestion and gas. Celery, fennel, asparagus, and lemon, are natural diuretics.
  • Warm water between meals: drinking cold drinks with food dilutes your gastric juices and hampers digestion.
  • Digestive enzymes: sometimes your body struggles to make enough of it’s own natural digestive enzymes. Supplementing can help [Source: PubMed].
  • Probiotics (friendly bacteria), but be aware that they could worsen your bloating (especially at first), depending on the type of bacteria and your individual body chemistry. It takes a bit of trial and error to find the right one for you.

Symptom #2: Diarrhoea

Normal stools are usually solid because the small intestine and colon are doing their job well: absorbing nutrients, fluid and salts from the food you’ve eaten.

With diarrhoea, it’s clear that something has gone wrong with your digestion. Sometimes, bacteria, viruses or toxins damage the lining of your gut so your body flushes water into your bowel. Your stools become loose and watery because your gut wants to get rid of whatever it is that’s irritating it.

In acute (short lasting) diarrhoea, symptoms come on suddenly but usually clear up within five to 10 days. Chronic (long lasting) diarrhoea continues longer than 4 weeks. You should always tell your GP if your diarrhoea doesn’t go away.

Whether your diarrhoea is acute or chronic, your gut is trying to expel something it doesn’t like. Of course, the question is why that’s happening. When you know that, you can address the root cause and hopefully stop the symptoms.

There is an almost endless list of reasons why you could have diarrhoea. Like bloating, a common reason is dysbiosis, either in your small or large intestine. 

Our Gut Health Tests reveal your levels of friendly and potentially less-friendly bacteria in your large intestine, and whether or not you have parasites or an overgrowth of candida (an opportunistic yeast). Confirming these or ruling them out is a crucial step on the road to tackling diarrhoea.

Remedies for diarrhoea symptoms

  • Saccharomyces boulardii (a friendly yeast) [Source: PubMed]
  • Real fermented sauerkraut juice or other fermented vegetable juice [Source: PubMed]
  • Soluble fibre, contained in bananas, squash, carrots and sweet potatoes [Source: PubMed]
  • Activated charcoal (short term use only as it absorbs water and nutrients) away from meals and any supplements [Source: PubMed].

Symptom #3: Constipation

The NHS says that it’s normal to have as little as three bowel movements a week, but many experts disagree.

“Optimal bowel transit time is 12 to 24 hours,” says Liz Lipski, PhD, author of Digestive Wellness: How to Strengthen the Immune System and Prevent Disease Through Healthy Digestion. “Three bowel movements a week amounts to a transit time of 56 hours, which is way too long.”

There’s no simple answer to the question of why you have constipation. However, possible reasons include:

  • SIBO
  • A low water intake
  • Chronic stress
  • Low fibre intake (but not always)
  • Dysbiosis
  • Food intolerances
  • Neurological problems

To find out more about constipation, check out our article Constipation and the NHS: what are your options?

Remedies for constipation symptoms

  • Magnesium citrate or oxide at 500mg to two grams per night. One gram is a common effective dose [Source: PubMed]
  • Digestive bitters (as before)
  • Fat intake (large intestine motility is increased by fat): butter, coconut or olive oil, or egg yolks are all nutritious fats [Source: PubMed]
  • Increase insoluble fibre: nuts, peas, green beans and flaxseeds [Source: PubMed]
  • Warm water or herbal tea in the morning, drunk slowly (stimulates your large intestine)
  • Potassium (retains water in the stool): fresh homemade juice using cucumbers, tomatoes and carrots. Avocados and bananas are high in potassium

Symptom #4: Reflux

If you ask anyone what causes heartburn, they’re likely to say “too much stomach acid.” That sounds sensible, but it actually makes no sense when you look a bit deeper. 

Reflux is more common in older people, but our stomach acid production slows down as we age [Source: PubMed]. So why do older people, with less stomach acid, get heartburn and reflux?

One of the causes of reflux is actually low stomach acid [Source: PubMed]. The reason acid suppressants like Gaviscon or Omeprazole work is because the stomach acid is in the wrong place. Symptoms of heartburn are caused by stomach acid refluxing into the oesophagus, so eliminating stomach acid with drugs relieves those symptoms.

But that doesn’t fix the issue of why the acid is in the wrong place, which according to recent research, is as a result of high pressure in the abdomen [Source: PubMed]. That pressure pushes the stomach contents, including acid, through the ‘trapdoor’ at the bottom of your oesophagus and up into your throat.

Some experts now argue that it’s carbohydrate malabsorption that leads to bacterial overgrowth. Those bacteria release gases that increase pressure in your abdomen, which drives reflux [Source: PubMed]. 

Ironically, low stomach acid is a big driver of bacterial overgrowth (otherwise known as SIBO). It may sound unlikely, but many people with acid reflux have found relief by actually increasing their stomach acid with supplements and herbal extracts.

Looking for advice? Speak to an expert.


Remedies for the symptoms of acid reflux

  • One half to one teaspoon of baking soda in glass of water 
  • Bitters, as before
  • Apple cider vinegar: one tablespoon in glass of water before meals 
  • Betaine HCl capsules: One at the start of protein containing meals. You can increase the number of pills until you feel a heaviness or burning [Source: PubMed]

Symptom #5: Food intolerances

Food intolerances are frustrating and confusing. You could eat ice cream and sandwiches when you were a child, so why do they give you uncomfortable symptoms now?

Once again, the answer isn’t simple. Here are a few reasons why you could have developed food intolerances:


When you have SIBO, you have too many bacteria living in your small intestine. There aren’t meant to be high numbers of bacteria there, mainly because the small intestine isn’t designed to ferment your food. That’s the job of your large intestine, where there are over a million times more bacteria.

Too many bacteria in your small intestine means fermentation is happening there, which then causes you symptoms like bloating, diarrhoea and pain. Some foods are more fermentable than others, like garlic, onion, chickpeas and apples, for example. Once you lower your bacterial load, your intolerances should improve.

Large intestinal dysbiosis

While fermentation is supposed to happen in the large intestine, you can have too much of a good thing. If you have an imbalance in the microbial communities that live there, certain types can cause symptoms when you eat particular foods, like in the example above.

An issue with the immune system in your gut

The science is still very young on this, but it appears that some people’s immune systems react to certain foods and ‘attack’ their guts when they eat them [Source: PubMed].

Remedies for the symptoms of food intolerances

Tackling SIBO or dysbiosis often takes care of food intolerances. 

If your immune system is at play, digesting foods poorly will make food intolerances worse. We recommend that you try:

Digestive enzymes

Enzymes are necessary to break apart chains of amino acids so proteins are completely digested. Effective digestive enzymes include pepsin, bromelain, proteases, and more.

Immune system support

Certain flavonoids (beneficial plant compounds) have been shown to help block the immune response. They include quercetin, luteolin, apigenin, and lycopene [Source: PubMed].

Symptom #6: Allergies

There is little doubt today that poor gut health plays a large role in the development and progression of allergies [Source: PubMed].

If you have an allergy, many researchers now agree that you will also have intestinal permeability, or ‘leaky gut’. In other words, it’s unlikely that you have an allergy unless you also have a leaky gut [Source: PubMed].

With leaky gut, the digestive tract becomes inflamed, allowing undigested foods, bacteria, yeasts, and other toxins into the bloodstream. The immune system launches an attack on these toxins, which creates inflammation throughout your body. For many people, this happens every time they eat [Source: PubMed].

Remedies for allergy symptoms

While allergies can’t technically be cured, you can lessen the symptoms by addressing your leaky gut. You could try:

A gluten-free diet

Gluten has been shown to open up the tight junctions in some people’s gut lining, resulting in leaky gut [Source: PubMed].


Researchers have found that even a low dose of oral glutamine could improve intestinal permeability after strenuous exercise [Source: PubMed].


Zinc is able to modify the tight junctions of the intestinal lining, helping to limit gut permeability [Source: PubMed].


Collagen peptides are best, as they are a more easily digestible and bioavailable form of collagen. Collagen peptides can prevent breakdown of the intestinal lining [Source: PubMed].


When fibre is fermented by your gut microbes, it creates a short-chain amino acid called butyrate. You can also supplement with butyrate. It has been shown to stimulate mucus production and tighten the junctions in your gut lining [Source: PubMed].

Key takeaways

The evidence on the links between gut health and disease—both inside and outside the gut—are rocketing.

 fIf you’re concerned about your gut health, or you have any of the conditions we’ve talked about here, these steps are a great place to start.

Getting great gut health is one of the best things you can do for your body and mind, no matter what your symptoms are. If you think you could have an unhealthy gut, start with simple changes, like cutting out processed foods. Always talk to your doctor if you’re worried about any new symptoms.

In a nutshell, for great gut health:

  • Rule out any serious conditions with your doctor
  • Rule out or confirm any conditions like SIBO, parasites or bacterial or fungal overgrowths with functional testing
  • Eat a whole foods diet, free of processed foods
  • Experiment with restrictive diets (with the help of a professional, and in the short-term) to identify food intolerances
  • Trial appropriate supplements, starting ‘low and slow’ working with a Functional Medicine Practitioner or Registered Nutritional Therapist for support and guidance


Alexandra Falconer MA (Dist) DipCNM mBANT is a Registered Nutritional Therapist specialising in IBS and related conditions. A graduate of Brighton’s College of Naturopathic Medicine, she is committed to fighting the root causes of chronic illness and bringing functional medicine to everyone who needs it.

Before her natural health career, Alex was a journalist and copywriter. She continues to write for magazines and media agencies, and now combines her two great passions—writing and health—by creating content that empowers people to claim their right to a healthy body and mind.


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