Heartburn occurs when stomach acid backs up into the tube that carries food from your mouth to your stomach (esophagus). Normally when you swallow, a band of muscle around the bottom of your esophagus (lower esophageal sphincter) relaxes to allow food and liquid to flow down into your stomach.

What is heartburn caused by?

The most common cause is food that's acidic or high in fat—like citrus fruits, tomatoes, onions, chocolate, coffee, cheese, and peppermint. Spicy foods or large meals can also be the root of distress. Other sources of heartburn include aspirin or ibuprofen, as well as some sedatives and blood pressure medications.

How does a heartburn feel?

Heartburn typically feels like a burning in the center of your chest, behind your breastbone. When you have heartburn, you may also feel symptoms like: A burning feeling in your chest that can last anywhere from a few minutes to a couple of hours. Pain in your chest when you bend over or lay down.