A hernia involving the stomach is called a hiatal hernia (sometimes spelled “hiatus hernia”). The name comes from the hiatus, a small opening in the diaphragm where the esophagus passes through to connect to the stomach. When part of the stomach pushes up through that opening into the chest cavity, the result is a hiatal hernia. It’s one of the most common digestive conditions, and prevalence climbs steadily with age, from about 2.4% of people in their 50s to nearly 17% of those in their 80s and 90s.
How the Stomach Moves Out of Place
Your diaphragm is a dome-shaped muscle separating your chest from your abdomen. The esophagus passes through a roughly 2-centimeter gap in the diaphragm called the esophageal hiatus. A band of connective tissue, the phrenoesophageal ligament, normally anchors the junction between the esophagus and stomach in its proper position below the diaphragm.
Over time, that ligament can weaken or stretch. When it does, the opening in the diaphragm widens, and part of the stomach slides upward into the chest. The hiatus naturally narrows when abdominal pressure rises (during coughing or heavy lifting, for example), but a weakened opening loses that ability, making herniation more likely.
Types of Hiatal Hernia
Not all hiatal hernias behave the same way. Doctors classify them into four types based on which part of the stomach moves and how far it travels.
- Type I (sliding hernia): The most common form by far. The junction where the esophagus meets the stomach slides upward into the chest. Because the valve at the bottom of the esophagus is no longer held in place by abdominal pressure, it becomes a less effective barrier against acid reflux.
- Type II (paraesophageal hernia): The esophageal junction stays in its normal spot, but a portion of the stomach bulges up alongside the esophagus into the chest. This type is less common but more likely to cause complications.
- Type III (mixed): A combination of Types I and II. Both the esophageal junction and a section of the stomach migrate into the chest.
- Type IV: A large defect that allows other abdominal organs, not just the stomach, to push through the hiatus.
Causes and Risk Factors
The two biggest risk factors are age and obesity. Hiatal hernias are most common in people over 50, largely because the tissues around the hiatus gradually weaken over decades. Carrying excess weight increases pressure inside the abdomen, which pushes against the diaphragm from below.
Repeated or sustained spikes in abdominal pressure also contribute. Chronic coughing, frequent vomiting, straining during bowel movements, and regularly lifting heavy objects all force the stomach upward against the diaphragm. Some people are born with an unusually large hiatus, which makes herniation easier from the start.
Symptoms to Recognize
Many people with a hiatal hernia never know they have one. Sliding hernias in particular often produce no symptoms at all and are discovered incidentally during imaging for something else. When symptoms do appear, they’re almost always related to acid reflux: heartburn, a sour taste in the back of the throat, difficulty swallowing, or a feeling of food getting stuck behind the breastbone.
Larger hernias, especially paraesophageal types, can cause a sense of fullness after eating small amounts, chest pain, or shortness of breath if the herniated stomach presses on the lungs. In rare cases, a paraesophageal hernia can become strangulated, meaning the blood supply to the trapped portion of stomach gets cut off. Warning signs include sudden severe abdominal pain, nausea and vomiting, and skin around the area changing color. This is a medical emergency.
How It’s Diagnosed
Two tests are most commonly used. A barium swallow involves drinking a chalky liquid that coats the inside of your esophagus and stomach, making their outlines visible on X-ray. This clearly shows whether part of the stomach has moved above the diaphragm. The second option is an upper endoscopy, where a thin tube with a camera is passed down the throat to directly view the esophagus and stomach lining, checking for inflammation or other damage from acid exposure.
Many hiatal hernias are also spotted on CT scans done for unrelated reasons, which is how the condition often gets diagnosed in people without symptoms.
Treatment and Lifestyle Changes
Small, symptom-free hiatal hernias generally don’t need treatment. When acid reflux symptoms are the main problem, the first line of management is lifestyle adjustments. Eating several smaller meals instead of two or three large ones reduces the amount of pressure on the stomach at any given time. After eating, staying upright for two to three hours before lying down gives your stomach time to empty, which limits reflux.
Certain foods tend to make symptoms worse: chocolate, mint, alcohol, spicy dishes, high-fat meals, and caffeinated drinks like coffee, tea, and energy drinks. If heartburn disrupts your sleep, raising the head of your bed 15 to 20 centimeters (about 6 to 8 inches) using bed frame blocks or a foam wedge under the mattress helps gravity keep acid in the stomach. Extra pillows alone don’t work because they bend the body at the waist rather than elevating the entire upper torso.
Over-the-counter acid-reducing medications can manage reflux symptoms effectively for many people. When lifestyle changes and medication aren’t enough, or when a paraesophageal hernia is large enough to risk complications, surgery becomes an option. The most common procedure wraps the upper part of the stomach around the lower esophagus to reinforce the valve and pull the stomach back below the diaphragm. About 10% of people who have this surgery eventually need a second operation, but for the majority, it provides lasting relief.