Indigestion is a general term used to describe discomfort in the upper abdomen. It's not a disease, but rather a collection of symptoms. You may notice a burning sensation in your upper abdomen, nausea, bloating and belching.

Here's what causes these symptoms — and how to prevent them.

If you eat too much of any food, you can wind up with an upset stomach, particularly if you overindulge in fatty or spicy foods. Eating too quickly has the same effect. Alcohol and stress can also take a toll.

Persistent indigestion may point to other digestive conditions:

• Heartburn. When stomach acid backs up into the esophagus — an event known as acid reflux — you may experience heartburn. This burning pain in the upper abdomen and under the breastbone may be accompanied by nausea and an acid or sour taste in your mouth.
• Peptic ulcers. Peptic ulcers are open sores that develop on the lining of the stomach, upper small intestine or esophagus. They may cause burning pain anywhere from your navel to your breastbone. Many peptic ulcers are caused by the bacterium Helicobacter pylori (H. pylori). Others are caused by regular use of certain pain relievers, such as aspirin, naproxen or ibuprofen.
• Gastritis. Gastritis is inflammation of the lining of your stomach, which you may experience as a gnawing or burning pain in your stomach or upper abdomen. Regular use of aspirin or certain other pain relievers can irritate your stomach. Drinking too much alcohol can have the same effect. Some cases of gastritis are caused by an infection with the same bug that causes peptic ulcers.
• Gallstones. Gallstones are solid deposits of cholesterol or calcium salts that form in your gallbladder or nearby bile ducts. They often cause no symptoms and require no treatment. Sometimes, however, gallstones cause chronic indigestion, abdominal pain, nausea and vomiting.
• Stomach cancer. The earliest sign of a stomach tumor may be microscopic internal bleeding, which may only be detected by tests that check your stool for blood. Later, signs and symptoms may resemble those of a peptic ulcer. Stomach cancer is uncommon in the United States.

Healthy lifestyle choices may help prevent mild indigestion.

• Eat smaller, more frequent meals. Chew your food slowly and thoroughly. Avoid anything that triggers indigestion, such as fatty and spicy foods, carbonated beverages, caffeine and alcohol.
• Maintain a healthy weight. Excess pounds put pressure on your abdomen, pushing up your stomach and causing acid to back up into your esophagus.
• Exercise regularly. With your doctor's OK, aim for 30 to 60 minutes of physical activity on most days of the week. It can be as simple as a nightly walk after dinner.
• Manage stress. Create a calm environment at mealtime. Practice relaxation techniques such as deep breathing, meditation or yoga. Spend time doing things you enjoy.

Mild indigestion is usually nothing to worry about. Consult your doctor if the discomfort is persistent, severe or accompanied by:

• Weight loss
• Vomiting
• Black, tarry stools
• Shortness of breath, sweating or pain radiating to the jaw, neck or arm

Treatment will depend on what's causing your symptoms.