What causes heartburn?

What causes heartburn and what triggers heartburn are two different discussions. The cause is the failure of your lower esophageal sphincter to tighten as it’s supposed to. Eating too much too fast, obesity and pregnancy can contribute to the problem. Certain foods, stress, not getting enough sleep and smoking can trigger heartburn.

Acid reflux, or heartburn, can happen when there is large amount of pressure in the stomach (such as after a big meal) or if the valve at the lower esophageal sphincter becomes inappropriately weak after consuming certain substances (caffeine, chocolate, alcohol, etc.). Frequently, both mechanisms of action are the cause. When reflux occurs, the lining of the esophagus is not designed to handle this displacement of acid, and it can become irritated and that irritation causes heartburn. 

Heartburn, or acid reflux, is caused by acid in the stomach backing up into the esophagus. The fluid in your stomach is very acidic; with a pH of 1.5 to 3.5, the acidity is in the same range as lemon juice or vinegar. While this acid helps you digest and breakdown foods, it can be very toxic to the esophagus. A valve called the lower esophageal sphincter (LES) is our body’s protection against stomach acid. Normally, the LES remains contracted and closed which prevents the back-up or reflux of stomach acid into the esophagus. As we get older the LES can become weaker and is unable to remain closed all of the time. This allows the reflux of stomach acid into the esophagus, which leads to irritation. For some people, this occurs daily.

Dr. Randolph P. Martin, MD
Cardiologist (Heart Specialist)

If you are overweight, wear tight fitting clothes or are pregnant you may experience heartburn due to the increase of pressure on your abdomen. Watch this video to learn more from Dr. Randy P. Martin about what causes heartburn.

Heartburn is a symptom. It's that painful burning sensation you feel in your chest area when you experience acid reflux—stomach acid creeping back up into your esophagus.

Normally, a muscular valve at the end of the esophagus, called the lower esophageal sphincter (LES), helps keep what you eat and drink—as well as digestive juices—in your stomach, where it all belongs. But when the LES is weak or otherwise doesn't work right, acid reflux occurs. Stomach contents move back up into the esophagus, and you experience what is known as heartburn. Heartburn hurts because your esophagus doesn't have the same protective lining that your stomach does.

About 60 million people in the US experience heartburn once a month, and as many as 15 million people may experience heartburn every day.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.