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Heartburn is a burning pain in your chest. This pain is caused by stomach acid rising from your stomach into your oesophagus (the pipe that takes food from your mouth to your stomach).
This can cause:
- Burning pain in the middle of your chest
- Pain which is worse when you bend over or lie down
- Burning pain that radiates into your back
By learning more about the causes of, tests for, and treatment for heartburn, you can understand it better and make informed decisions to get back on track.

There are several possible causes of heartburn, and it’s important to find out what’s causing yours.
Here are the main causes of heartburn:
Gastroesophageal reflux disease (GORD)
Hiatus hernia, when part of your stomach moves up into your chest
Surgery you’ve had in the past (especially bariatric surgery)
Certain foods and drinks, such as alcohol, coffee, chocolate, and fatty or spicy foods
Being overweight
Smoking
Pregnancy
Stress or anxiety
Medication, such as anti-inflammatory painkillers
Overgrowth of bacteria in your small intestine (this is called SIBO)


Diagnostic testing allows us to pinpoint the exact cause so we can recommend the right solution.
At the Functional Gut Clinic, we use the following highly accurate and trusted diagnostic tools, to identify the underlying cause of your heartburn:
Oesophageal manometry – which measures the function of your oesophagus (food pipe)
24-hour pH impedance monitoring – which looks at whether you have any reflux
Carbohydrate malabsorption breath test – which finds out if you have certain food intolerances (lactose or fructose)
Small intestinal bacterial overgrowth (SIBO) breath test – which finds out if you have an overgrowth of bacteria in your small intestine (called SIBO)
Gastric emptying test – which measures how quickly food leaves your stomach

Heard of the gut microbiome? It’s the community of trillions of bacteria, viruses, fungi, and other microbes living in your gut. The microbiome is crucial to your health. When it's disrupted, it doesn’t just affect your digestion; it can affect everything from your mood to your skin.
When this topic comes up, people talk about diet, exercise, alcohol, and even artificial sweeteners. Each of these factors can alter your gut microbiome. But there’s one factor that gets forgotten: menopause.
Women often blame their menopause symptoms on their hormonal changes. And yet, the latest evidence suggests that your gut bacteria might play a surprising role in menopause, offering the potential for new and effective treatments.
Your gut microbiome and the rest of your body constantly exchange signals. What affects one naturally impacts the other.
A big part of this two-way communication is hormones.
During menopause, your reproductive hormones, like oestrogen and progesterone, begin to fall. This can be slow at first, or quite dramatic. But it has big implications for your gut microbiome.
Inside your gut, there’s a group of gut bacteria that process and recycle oestrogen. They’re known as the “estrobolome.” These bacteria determine how much oestrogen is recycled versus excreted from the body. That means any changes in these bacteria can influence menopausal symptoms.
The consequences are wide-reaching. Lower oestrogen levels can affect bone density, metabolic health, cholesterol levels, and cardiovascular disease.
Menopause is one potential factor causing shifts in your gut microbiome. But it’s not the only one.
From the moment you’re born, your gut microbiome is changing. The first big shift comes when you switch from breast milk to food. Gradually, you then accumulate different species throughout childhood.
The next stage, especially for women, is during puberty. The production of sex hormones increases gut microbiome diversity in females more than in males. After menopause, however, a women’s gut microbiome tends to resemble that of a male’s more than her own pre-menopausal profile.
There are natural fluctuations over your lifetime as well. Antibiotics, processed foods, healthy periods, and more can all influence your gut bacteria, subtly shifting the composition.
Your ovaries secrete natural oestrogens throughout your life. You might get a little extra from the contraceptive pill if you take this too. These are filtered from your blood by the liver, which then get excreted in bile.
The same is true for progesterone.
In your gut, the estrobolome helps “recycle” oestrogens. It does this by unbinding the compounds your liver used to metabolise them, allowing them to re-enter your blood supply.
But there’s one part not mentioned. Gut bacteria rely on the flow of oestrogens in the first place. When this starts to decline, the estrobolome becomes less active. With fewer oestrogens circulating, the recycling process weakens, so even less oestrogen is returned to the bloodstream.
It does mean that gut bacteria play a disproportionate role in your oestrogen levels as natural hormone production declines. So, if you can support these bacteria in other ways, it can help soften menopausal symptoms.
When falling oestrogen levels combine with shifts in gut bacteria, the effects can ripple far beyond digestion. Some of the most common consequences include:
More digestive discomfort. Changes in bacterial balance can lead to bloating, constipation, diarrhoea, or food sensitivities that seem to appear out of nowhere.
Worsening metabolic health. A disrupted microbiome has been linked to weight gain, insulin resistance, and a higher risk of type 2 diabetes, all of which become more common after menopause.
Bone and heart health. Lower oestrogen levels are closely related to declining bone mass and higher cholesterol levels. This increases the risk of osteoporosis and cardiovascular disease.
Mood, skin, and inflammation changes. Women commonly notice low mood, joint aches, or skin flare-ups during menopause. But these symptoms are also linked to gut dysbiosis.
Menopause is one of the best times to support your microbiome. Here’s what you can do:
Eat lots of fibre. Fruits, vegetables, legumes, and whole grains fuel your gut microbiome. Choosing a diet rich in different plant species supports microbial diversity.
Include fermented foods. Foods like yoghurt, kefir, kimchi, and sauerkraut contain helpful microbes that can help recolonise your gut.
Protect sleep and lower stress. Hormone changes can cause sleep issues or rising stress. Try to counteract these symptoms to safeguard your microbiome.
Consider HRT. It’s not yet clear whether HRT reverses microbiome changes, but early research suggests it may influence gut composition.
Most of all, get your gut microbiome tested. The Functional Gut Clinic offers personalised microbiome testing for women experiencing menopause. You’ll receive personalised recommendations and dietary guidance to help support your gut.
Read the next interesting article: Signs of Poor Gut Health in Kids
Heartburn is often experienced after eating and can last anywhere from a few minutes to several hours. The stomach releases more acid after eating certain foods, including spicy dishes, fatty foods, citrus fruits, tomato-based products, garlic, and caffeinated drinks. The more acid that is produced, the greater the risk of heartburn.
Other factors include obesity, smoking, stress, pregnancy, and eating too close to bedtime.



Heartburn primarily causes an uncomfortable or burning sensation in the middle of your chest. You may also experience:
A burning sensation in your throat
A strong acidic or sour taste in your mouth
Difficulty swallowing (dysphagia)
A feeling of pressure or pain behind your breastbone
Repeated coughing
Hoarse voice
In addition to these symptoms, the pain from the acid can get worse when lying down or bending over. This is because the acid flows out of the stomach and into the oesophagus. Whenever you lie down, you increase the risk of heartburn-related symptoms.
Constant heartburn is a sign of a severe underlying condition. Most people experience heartburn in episodic attacks – usually after consuming certain foods. If the heartburn is persistent, it’s crucial to speak to a medical professional. You can also consider organising a test via The Functional Gut Clinic (see below).


Heartburn occurs when the contents of the stomach enter the oesophagus (the food pipe connecting your stomach to your throat). Usually, the stomach contents are prevented from going back into the oesophagus by a juncture called the lower oesophageal sphincter. However, in some people, this sphincter doesn’t function properly.
Heartburn is a symptom of gastroesophageal reflux disease (GORD). GORD simply refers to the backflow of acid from the stomach into the oesophagus. GORD is the condition; heartburn is the symptom.

Several factors increase the risk of heartburn. The causes of heartburn and GORD either increase acid production within the stomach or affect the functioning of the lower oesophageal sphincter. These include:
Hiatal hernia. A hiatus hernia involves a part of your upper stomach penetrating through the diaphragm (the layer of muscle separating your chest from your stomach). This usually occurs due to a weakness or tear.
Pregnancy. If you become pregnant, the increased pressure during the third trimester (and sometimes earlier) forces the stomach contents backwards, causing heartburn.
Surgery. Previous surgery, especially bariatric surgery, increases the risk of not only heartburn but also a hiatus hernia.
Smoking. Smoking is closely linked to heartburn and GORD. People who quit smoking notice a significant reduction in heartburn symptoms.


Overweight or obesity. Being overweight or obese is a major risk factor for GORD. This is likely due to the increased pressure in the stomach alongside a diet high in fatty, processed foods.
Medications. Certain medications, such as anti-inflammatory painkillers (e.g., ibuprofen or aspirin), sedatives, and blood pressure medications, can increase your risk of heartburn.
Stress or anxiety. An increase in stress or anxiety can increase acid production in some people, leading to heartburn. It’s often accompanied by another factor.
Small intestine bacterial overgrowth (SIBO). Excessive bacterial growth in the small intestine leads to increased abdominal pressure and subsequent acid reflux, which can cause heartburn. Managing SIBO often reduces these symptoms.
Acid production is a normal part of the stomach’s function. The acid helps digest food. Certain foods require more acid to digest, triggering an increased production in the stomach.
For most people, this isn’t an issue as the acid flows into the small intestine. However, if you struggle with heartburn and GORD, then it’s sensible to limit or avoid certain foods. These include:
Citrus fruits (like oranges and grapefruits)
Tomatoes and tomato-based products
Spicy foods
Garlic and onions
Chocolate
Mint
Fatty or fried foods
Caffeinated beverages (such as coffee and tea)
Carbonated drinks
Alcohol
It’s not just the food. Eating an excessively large meal, wearing tight clothes, and lying down soon after eating can increase the risk of heartburn. If you’re experiencing persistent heartburn, it’s often linked to diet rather than another factor.

No. Heartburn specifically refers to the burning sensation in the chest. GORD is the underlying condition involving the backflow of acid. Heartburn is a symptom of GORD. Acid reflux is sometimes used as shorthand for GORD – however, not every attack of acid reflux is an example of GORD.
Acid reflux refers to any episode of acid backflowing into the oesophagus. If the episodes occur two or more times a week, it is diagnostic for GORD. Most people experience acid reflux episodes occasionally. This can increase in frequency as acid reflux progresses to GORD. You should speak to a doctor if you notice this change.

Heartburn is always caused by the backflow of acid into the oesophagus. Several other conditions can create a similar sensation. For example:
Oesophageal ulcers. Ulcers occur due to erosion of the oesophageal lining. Often associated with acid reflux or overusing anti-inflammatory medications.
Oesophagitis. Severe inflammation of the oesophagus is closely linked to GORD. However, it can also be caused by medications and infections. An allergic condition known as eosinophilic oesophagitis can also cause heartburn.
Functional heartburn. Unlike the other conditions, this isn’t a problem with your oesophagus or stomach. It’s caused by a disorder of the gut-brain connection. It involves the same heartburn symptoms but without any signs of acid reflux or inflammation. It’s connected to overactive nerves.


Heartburn is not a permanent condition. It lasts as long as the acid is present to irritate the oesophagus and throat. Most people experience heartburn and GORD for between a few minutes to several hours. The timespan often depends on the underlying cause. For example, if your heartburn is due to your diet, it might go away within a few minutes. In contrast, if you have a hiatus hernia, the heartburn might persist for much longer, even after standing up.
Constant heartburn is a rare symptom. It’s a concerning sign, as the acid can continue to damage your oesophagus. If you’re constantly feeling heartburn (or using lots of antacids), then it’s critical to speak to a doctor.
Most cases of heartburn aren’t serious. It’s common to experience heartburn after a large meal or eating certain foods. However, if the heartburn becomes repeated or constant, it can cause long-term damage. Usually, the damage caused by acid reflux heals like any injury. If it happens regularly, then the oesophagus lining can become permanently injured.
Potential long-term complications include:
Oesophageal strictures. The lining of the oesophagus becomes replaced with scar tissue due to repeated inflammation. This scar tissue causes a narrowing of the oesophagus (stricture), which prevents food from getting through.
Intestinal metaplasia. The tissue lining of the oesophagus undergoes a change to look more like the lining of your intestines, protecting it from damage. It is called Barrett’s oesophagus and is a precancerous condition.
Oesophageal cancer. Cancer is a rare complication of GORD and heartburn. It occurs due to persistent inflammation and cellular changes. The longer your heartburn persists, the greater the risk of cancer.
Heartburn and GORD can also indicate problems in your stomach. For example, excess acid production can lead to gastritis (stomach inflammation) and stomach ulcers. It may also aggravate preexisting conditions such as asthma.

The following tests may be used to diagnose what is causing your heartburn:
Oesophageal manometry – which measures the function of your oesophagus (food pipe)
24-hour pH impedance monitoring – which looks at whether you have any reflux
Carbohydrate malabsorption breath test – which finds out if you have certain food intolerances (lactose or fructose)
Small intestinal bacterial overgrowth (SIBO) breath test – which finds out if you have an overgrowth of bacteria in your small intestine (called SIBO)
Gastric emptying test – which measures how quickly food leaves your stomach
The following tests may be used to diagnose what is causing your heartburn:
Oesophageal manometry – which measures the function of your oesophagus (food pipe)
24-hour pH impedance monitoring – which looks at whether you have any reflux
Carbohydrate malabsorption breath test – which finds out if you have certain food intolerances (lactose or fructose)
Small intestinal bacterial overgrowth (SIBO) breath test – which finds out if you have an overgrowth of bacteria in your small intestine (called SIBO)
Gastric emptying test – which measures how quickly food leaves your stomach

Most people who experience occasional heartburn symptoms can benefit from lifestyle changes. This involves limiting exposure to potential triggers. You might want to try:
Avoiding trigger foods, such as fatty foods or caffeinated beverages
Eating smaller meals
Avoiding tight clothing
Avoiding lying down immediately after eating
Quitting smoking and alcohol consumption.
Often, people find that small changes to their diet can stop or reduce episodes of heartburn. If the heartburn continues, it’s usually a sign that something else is going on. It’s crucial to get to the bottom of your symptoms; otherwise, they will persist.



As heartburn is caused by acid, neutralising this acid relieves symptoms. The primary treatment for heartburn is an over-the-counter (OTC) antacid, such as Gaviscon or Alka-Seltzer. These medications provide immediate relief from your symptoms – perfect for tackling a sudden acid reflux attack. If you experience constant heartburn, it’s sensible to carry antacids with you. However, excessive use of antacids can cause other problems.
Your doctor may prescribe medications that prevent acid production. This includes:
Proton Pump Inhibitors (PPIs). These medications reduce stomach acid production by blocking the enzyme in the stomach lining that produces acid. Common examples include omeprazole, esomeprazole, and pantoprazole. PPIs are used to treat GORD by allowing the oesophagus to heal and preventing further damage.
H2 Receptor Antagonists. These drugs work by blocking H2 receptors on stomach cells that signal the production of acid. This results in decreased stomach acid output. Examples include ranitidine, famotidine, and cimetidine. They are effective in relieving GORD symptoms and are generally used for milder cases.

In the majority of cases, lifestyle changes and medication are enough to prevent heartburn symptoms. If GORD doesn’t respond to medication, surgery might be a potential option. This can repair a hiatus hernia, strengthening the lower oesophageal sphincter and permanently preventing the backflow of acid.
Procedures include:
Nissen fundoplication. This procedure tightens the junction between the stomach and the oesophagus.
Transoral incisionless fundoplication. A similar procedure performed non-surgically using an endoscope.
LINX device. A tiny ring of magnets is placed around the junction between the stomach and oesophagus to prevent reflux. It’s a type of minimally invasive surgery.
Heartburn is extremely uncomfortable. However, most cases are relatively mild and treatable with antacids. Speak to a medical professional if:
You experience heartburn more than once a week
You have other associated symptoms
You have difficulty swallowing
Your heartburn persists despite treatment
You’re over the age of 60
You have a tight or squeezing chest pain
You cough up blood
Remember, occasional heartburn is relatively normal. But if you have constant heartburn, it’s crucial to get tested. The Functional Gut Clinic is highly experienced in diagnosing acid reflux. We’ll organise your test and provide advice on what to do next.

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Burning mid-chest, worse when bending or lying down

Difficulty going to the toilet, unusual stools, often with stomach ache or intestinal cramps, bloating, nausea or appetite loss

Feeling uncomfortably full and tight, excess belching/breaking wind, abdominal pain or gurgling

Bringing food or drink back up, difficulty swallowing, feeling that food or drink is stuck in your throat, horrible taste in your mouth

Dysphagia - difficulty swallowing, feeling that food or drink is stuck in your throat, horrible taste in your mouth

Loose or explosive stools, can’t get to a toilet in time

Cramps; sharp or dull pain, Bloating, Excessive belching, Nausea or vomiting

Stools leak unexpectedly, Can’t get to a toilet in time

Abdominal pain or cramping, bloating, changes in bowel habits and urgency, gas