A hiatal hernia occurs when the upper part of your stomach pushes up through your diaphragm and into your chest.

The diaphragm is a large muscle that lies between your abdomen and chest. You use this muscle to help you breathe. Normally, your stomach is below the diaphragm. However, in people with a hiatal hernia, a portion of the stomach pushes up through the muscle. The opening it moves through is called a hiatus.

This condition mostly occurs in people who are over 50 years old. It affects up to 60 percent of people by the time they’re 60, according to the Esophageal Cancer Awareness Association (ECAA).

What Causes a Hiatal Hernia?

The exact cause of many hiatal hernias isn’t known. In some people, muscle tissue may be weakened by injury or other damage. This makes it possible for your stomach to push through your diaphragm.

Another cause is putting too much pressure on the muscles around your stomach. This may happen when:

  • Coughing
  • Vomiting
  • Straining during bowel movements
  • Lifting heavy objects

Symptoms of a Hiatal Hernia

It’s rare for even fixed hiatal hernias to cause symptoms. If you do experience any symptoms, they are usually caused by stomach acid, bile, or air entering your esophagus. Common symptoms include:

  • Heartburn that gets worse when you lean over or lie down
  • Chest pain
  • Trouble swallowing
  • Belching

What is the connection between GERD and Hiatal Hernias?

Gastroesophageal reflux disease (GERD) occurs when the food, liquids, and acid in your stomach end up in your esophagus. This can lead to heartburn or nausea after meals. It’s common for people with a hiatal hernia to have GERD. However, that doesn’t mean either condition always causes the other. You can have a hiatal hernia without GERD or GERD without a hernia.