Heartburn: What It Is, Why Stomach Acid Causes the Burn, and How to Get Relief

Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026

Heartburn is a burning pain in the chest, just behind the breastbone, caused when stomach acid backs up into the esophagus [1]. It is usually worse after eating, in the evening, or when lying down or bending over, and it often comes with a bitter or acidic taste in the mouth. Occasional heartburn is common and can be managed with lifestyle changes and over-the-counter medicines. But heartburn that occurs more than twice a week, or that persists despite self-treatment, may signal gastroesophageal reflux disease (GERD), a condition that can damage the esophagus and deserves a doctor's evaluation [2].

Quick Answer: What is heartburn and how is it treated?

Heartburn is a burning chest pain behind the breastbone caused by stomach acid flowing back into the esophagus. Most people manage occasional heartburn with lifestyle changes and over-the-counter medicines. See a doctor if it occurs more than twice a week, persists despite medicines, or comes with difficulty swallowing, persistent vomiting or unexplained weight loss.

What the research says

• Reflux is common worldwide, and it may be increasing. A systematic review of population-based studies estimated that GERD (heartburn and/or regurgitation at least weekly, or clinician-diagnosed) affects 18.1% to 27.8% of people in North America, 8.8% to 25.9% in Europe, 8.7% to 33.1% in the Middle East, and 2.5% to 7.8% in East Asia, with evidence that prevalence has risen since 1995 (El-Serag et al., Gut, 2014 [3]).

• Lifestyle changes have measurable effects. In a systematic review, weight loss lowered time with esophageal acid exposure in two randomized trials (from 5.6% to 3.7% and from 8.0% to 5.5%); head-of-bed elevation reduced supine acid exposure from 21% to 15% compared with lying flat; and late evening meals increased it compared with early meals. Quitting smoking reduced reflux symptoms in normal-weight people in a large cohort (odds ratio 5.67) (Ness-Jensen et al., Clin Gastroenterol Hepatol, 2016 [4]).

• Acid-reducing medicines beat placebo, and proton pump inhibitors beat H2 blockers. A meta-analysis of 13 trials (3,433 people treated empirically for GERD and 2,520 with endoscopy-negative reflux disease) found that both drug classes relieved heartburn better than placebo in the short term. Standard-dose proton pump inhibitors outperformed H2 blockers (summary relative risk 0.55; 95% CI 0.44 to 0.68, favoring proton pump inhibitors), with a more pronounced benefit in people treated empirically (van Pinxteren et al., J Gen Intern Med, 2003 [5]).

What heartburn feels like

Heartburn is a burning pain in the chest, located just behind the breastbone. The discomfort is often accompanied by a bitter or acidic taste in the mouth. The pain is typically at its worst after eating, in the evening, or when you are lying down or bending over.

Occasional heartburn is common and is not a cause for alarm. Most people can manage the discomfort on their own with lifestyle changes and nonprescription medicines. The concern arises when heartburn becomes frequent or starts to interfere with your daily routine — that pattern can be a symptom of a more serious condition that requires medical care.

The core symptoms to recognize are summarized below.

Symptom	What it looks like
Burning chest pain	Located just behind the breastbone; usually occurs after eating and may occur at night
Positional worsening	Pain gets worse when lying down or bending over
Acidic taste	A bitter or acidic taste in the mouth

Table: The three hallmark symptoms of heartburn.

Heartburn vs. heart attack: When chest pain means an emergency

Chest pain may be a symptom of a heart attack, and the two can feel confusingly similar. Seek emergency help right away if you have severe chest pain or pressure, especially when it is combined with pain in the arm or jaw or difficulty breathing.

Heartburn (typical pattern)	Heart attack warning signs (seek help right away)
Burning pain behind the breastbone	Severe chest pain or pressure
Worse after eating, lying down, or bending over	Pain combined with pain in the arm or jaw
Bitter or acidic taste in the mouth	Combined with difficulty breathing

Table: How heartburn differs from heart attack warning signs. Because the symptoms can overlap, when in doubt, seek emergency care.

When to see a doctor

Even when chest pain is clearly not an emergency, certain patterns of heartburn warrant a medical appointment. Make an appointment with a healthcare professional if any of the following apply.

Warning sign	Why it matters
Heartburn occurs more than twice a week	Frequent reflux can signal GERD
Symptoms persist despite nonprescription medicines	You may need prescription medicine and further testing
Difficulty swallowing	Can indicate esophageal narrowing or damage
Persistent nausea or vomiting	A sign of a more serious underlying condition
Weight loss because of poor appetite or difficulty eating	Needs prompt evaluation

Table: The five situations in which heartburn should prompt a doctor's visit.

What causes heartburn

Heartburn happens when stomach acid backs up into the tube that carries food from the mouth to the stomach, called the esophagus.

Normally, swallowing works like a well-timed valve. When food is swallowed, a band of muscle around the bottom of the esophagus — called the lower esophageal sphincter — relaxes to allow food and liquid to flow down into the stomach. Then the muscle tightens again.

If the lower esophageal sphincter is not working as it should, stomach acid can flow back up into the esophagus and cause heartburn. The acid reflux tends to be worse when you are bent over or lying down.

When this backflow happens frequently or constantly, it can lead to gastroesophageal reflux disease (GERD). Frequent or constant reflux is the bridge between an occasional annoyance and a chronic condition.

Reflux state	What it means
Occasional acid reflux	Stomach acid backs up from time to time, causing heartburn
Frequent or constant reflux	Can lead to gastroesophageal reflux disease (GERD)
Untreated chronic GERD	Can seriously damage the esophagus or cause precancerous changes

Table: The progression from occasional reflux to GERD.

Foods and situations that trigger heartburn

Certain foods and drinks can trigger heartburn in some people. The most commonly reported culprits are listed below.

Trigger category	Specific triggers
Spicy foods	Hot peppers and heavily spiced dishes
Vegetables	Onions
Fruit	Citrus products
Produce-based products	Tomato products, such as ketchup
Cooking style	Fatty or fried foods
Herbs and flavorings	Peppermint
Sweets	Chocolate
Drinks	Alcohol, carbonated beverages, coffee or other caffeinated beverages
Meal habits	Large or fatty meals

Being overweight or pregnant also can increase your risk of experiencing heartburn. Excess weight puts pressure on the abdomen, pushing up the stomach and helping acid back up into the esophagus.

Table: The food, drink, and lifestyle factors known to trigger heartburn.

Complications: What happens when heartburn is not managed

Heartburn that happens often and interferes with your routine is considered GERD. Left unchecked, GERD can cause real harm beyond daily discomfort.

The complications to understand are summarized below.

Complication	What it means
Esophageal damage	GERD can seriously damage your esophagus
Barrett's esophagus	GERD can lead to precancerous changes in the esophagus
Need for stronger treatment	GERD treatment may require prescription medicines
Possible procedures	Occasionally, GERD requires surgery or other procedures

Table: The complications and treatment escalation that chronic heartburn (GERD) can lead to.

How doctors diagnose the cause of your heartburn

To determine whether your heartburn is a symptom of GERD, a healthcare professional may recommend one or more of the following tests.

Test	What it does
X-ray	Views the shape and condition of the esophagus and stomach
Endoscopy	Views the esophagus with a tiny camera to check for irregularities; a tissue sample called a biopsy may be taken for analysis
Ambulatory acid probe test	Identifies when, and for how long, stomach acid backs up into your esophagus
Esophageal motility testing	Measures movement and pressure in the esophagus

During an endoscopy, a long, flexible tube (endoscope) is inserted down your throat and into your esophagus. A tiny camera on the end of the endoscope lets your doctor examine your esophagus, stomach, and the beginning of your small intestine (duodenum).

In an ambulatory acid probe test, an acid monitor is placed in your esophagus and connects to a small computer that you wear around your waist or on a strap over your shoulder. The monitor records exactly when and how long acid backs up.

Treatment options for heartburn

Many nonprescription medicines can help relieve heartburn. The three main categories work in different ways and have different strengths.

Medicine type	How it works	Speed and relief	Examples
Antacids	Neutralize stomach acid	Provide quick relief, but cannot heal an esophagus damaged by stomach acid	Over-the-counter antacid brands
H2 blockers	Reduce stomach acid production	Slower than antacids, but may provide longer relief	Cimetidine (Tagamet HB), famotidine (Pepcid AC)
Proton pump inhibitors	Reduce stomach acid production	Stronger acid reduction	Esomeprazole (Nexium 24HR), lansoprazole (Prevacid 24HR), omeprazole (Prilosec OTC)

Table: The three categories of nonprescription heartburn medicines.

If nonprescription treatments do not work or you rely on them often, see your healthcare provider. You may need prescription medicine and further testing.

Self-care: Eight lifestyle changes that ease heartburn

Lifestyle changes can help ease heartburn significantly. The evidence-supported changes are listed below.

Self-care change	The reason it helps
Maintain a healthy weight	Excess pounds put pressure on your abdomen, pushing up your stomach and causing acid to back up into your esophagus
Don't wear tightfitting clothing	Tight clothing puts pressure on your belly and the lower esophageal sphincter
Don't eat foods that trigger your heartburn	Spicy foods, citrus, and tomato products are common culprits
Don't lie down after a meal	Wait 2 to 3 hours before lying down
Don't eat late meals	Eat earlier and allow time for food to digest
Elevate the head of your bed	Helps if you regularly get heartburn at night or while trying to sleep; a wedge between mattress and box spring works better than extra pillows
Don't smoke or drink alcohol	Both decrease the lower esophageal sphincter's ability to function properly
Don't eat large meals	Instead, eat many small meals throughout the day

One detail is worth knowing: raising your head with additional pillows usually is not effective for nighttime heartburn. If elevating the head of your bed is not possible, the recommended alternative is to insert a wedge between your mattress and box spring to elevate your body from the waist up.

Table: The eight lifestyle changes recommended to ease heartburn.

Preparing for your appointment

If your heartburn is frequent or persistent, you may be referred to a doctor who specializes in disorders of the digestive system, called a gastroenterologist. Good preparation makes the visit more productive.

What you can do before the visit. Be aware of any pre-appointment restrictions, such as not eating solid food on the day before your appointment. Write down your symptoms, including any that may seem unrelated to the reason for the appointment. Make a list of all your medications, vitamins, and supplements. Write down your key medical information, including other conditions, and key personal information, including any recent changes or stressors in your life. Ask a relative or friend to accompany you to help remember what the doctor says, and write down questions to ask during the appointment.

Questions to ask your doctor. Consider asking about the most likely cause of your symptoms, whether your condition is likely temporary or chronic, what tests you need and whether they require special preparation, what treatments are available, whether you should remove or add foods to your diet, and how to best manage this condition together with any other health conditions you have.

What your doctor will ask. You may be asked when you first began experiencing symptoms and how severe they are, whether symptoms have been continuous or occasional, what improves or worsens them (and whether they are worse after meals or lying down), whether symptoms wake you at night, whether food or sour material ever comes up in the back of your throat, whether you experience nausea or vomiting, whether you have difficulty swallowing, and whether you have lost or gained weight.

What to do in the meantime. Try lifestyle changes to control your symptoms until you see a healthcare professional — for instance, avoid foods that trigger your heartburn and avoid eating at least two hours before bedtime.

Conclusion: Occasional burn is common — frequent burn deserves attention

Heartburn is a burning pain in the chest, just behind the breastbone, that happens when stomach acid backs up into the esophagus. Occasional episodes are common and usually manageable with lifestyle changes and over-the-counter medicines such as antacids, H2 blockers, and proton pump inhibitors. But heartburn that occurs more than twice a week, resists self-treatment, or comes with difficulty swallowing, persistent nausea or vomiting, or weight loss can be a sign of GERD — a condition that can damage the esophagus and cause precancerous changes if left untreated.

If you or a family member deals with frequent heartburn, schedule an evaluation rather than relying indefinitely on over-the-counter relief.

Frequently asked questions

What is heartburn?

Heartburn is a burning pain in the chest, just behind the breastbone, caused when stomach acid backs up into the esophagus — the tube that carries food from the mouth to the stomach. It is sometimes accompanied by a bitter or acidic taste in the mouth.

Why does heartburn happen at night or when lying down?

If the lower esophageal sphincter — the muscle band at the bottom of the esophagus — is not working as it should, stomach acid can flow back up into the esophagus. Gravity makes this reflux worse when you are bent over or lying down, which is why pain often peaks in the evening or at night.

Is occasional heartburn dangerous?

No. Occasional heartburn is common and no cause for alarm. Most people can manage the discomfort on their own with lifestyle changes and nonprescription medicines.

When should I worry about chest pain?

Chest pain may be a symptom of a heart attack. Seek help right away if you have severe chest pain or pressure, especially when combined with pain in the arm or jaw or difficulty breathing.

When should I see a doctor for heartburn?

Make an appointment if heartburn occurs more than twice a week, persists despite nonprescription medicines, or comes with difficulty swallowing, persistent nausea or vomiting, or weight loss from poor appetite or difficulty eating.

What foods trigger heartburn?

Common triggers include spicy foods, onions, citrus products, tomato products such as ketchup, fatty or fried foods, peppermint, chocolate, and alcohol, carbonated beverages, coffee, or other caffeinated drinks. Large or fatty meals are also a trigger.

What is the difference between heartburn and GERD?

Heartburn is the burning chest pain itself. Heartburn that happens often and interferes with your routine is considered gastroesophageal reflux disease (GERD), which may require prescription medicines and, occasionally, surgery or other procedures.

How is heartburn treated?

The main nonprescription options are antacids, which neutralize acid for quick relief; H2 blockers (cimetidine, famotidine), which reduce acid with longer relief; and proton pump inhibitors (esomeprazole, lansoprazole, omeprazole), which also reduce acid. If these do not work or you rely on them often, see a healthcare provider.

Can antacids heal a damaged esophagus?

No. Antacids may provide quick relief by neutralizing stomach acid, but they cannot heal an esophagus already damaged by stomach acid. That is one reason persistent symptoms need medical evaluation.

What lifestyle changes help heartburn?

Recommended changes include maintaining a healthy weight, avoiding tightfitting clothing, skipping trigger foods, waiting two to three hours after a meal before lying down, eating earlier and smaller meals, elevating the head of the bed, avoiding smoking and alcohol, and not eating large meals.

Related Reading

Nissen Fundoplication: GERD Surgery, Risks and Recovery explains Nissen fundoplication surgery for GERD.

Bravo Test: Wireless pH Monitoring for GERD, Prep and Results explains the wireless capsule test that measures acid reflux.

Learn more in our guide to TIF Procedure (Transoral Incisionless Fundoplication): How It Works, Risks and Recovery.

References

1. Mayo Clinic Staff. Heartburn - Symptoms and causes. Mayo Clinic. September 20, 2025. https://www.mayoclinic.org/diseases-conditions/heartburn/symptoms-causes/syc-20373223

2. Mayo Clinic Staff. Heartburn - Diagnosis and treatment. Mayo Clinic. September 20, 2025. https://www.mayoclinic.org/diseases-conditions/heartburn/diagnosis-treatment/drc-20373229

3. El-Serag HB, Sweet S, Winchester CC, Dent J. Update on the epidemiology of gastro-oesophageal reflux disease: a systematic review. Gut. 2014;63(6):871-880. PMID 23853213. https://doi.org/10.1136/gutjnl-2012-304269

4. Ness-Jensen E, Hveem K, El-Serag H, Lagergren J. Lifestyle intervention in gastroesophageal reflux disease. Clin Gastroenterol Hepatol. 2016;14(2):175-182.e1-3. PMID 25956834. https://doi.org/10.1016/j.cgh.2015.04.176

5. van Pinxteren B, Numans ME, Lau J, et al. Short-term treatment of gastroesophageal reflux disease. J Gen Intern Med. 2003;18(9):755-763. PMID 12950485. https://doi.org/10.1046/j.1525-1497.2003.20833.x

Further reading: Gavini S, Gupta M. Acid Reflux / GERD (Gastroesophageal Reflux Disease). American College of Gastroenterology. April 2025. https://gi.org/topics/acid-reflux/; American Heart Association. Warning Signs of a Heart Attack. American Heart Association. December 12, 2024. https://www.heart.org/en/health-topics/heart-attack/warning-signs-of-a-heart-attack.

Medical disclaimer

This article is for general informational purposes and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional about any medical condition.