Bloating: Causes, relief and when to see a doctor

Most people have experienced bloating from time to time. It often occurs after a large meal, around your menstrual cycle or because of something you ate.

But can this uncomfortable sensation in your abdomen ever be a sign of cancer?

The good news is that cancer is not a frequent cause of bloating. Bloating is actually quite common and often harmless. Read on to learn more about why it happens, how to relieve it and when to see a doctor.

What are the most common causes of bloating?

Bloating occurs most often due to food intolerances, motility disorders, and excess bacteria in the gut. A build-up of fluid in your abdomen called ascites also can cause you to feel bloated.

What actually causes your stomach to bloat?

There are many possible causes.

• Enzyme deficiencies make it hard for your body to break down and digest dairy and sugars properly. When these undigested foods reach your colon, bacteria ferment them and release excess gas.
• Celiac disease triggers an immune response that damages the small bowel when you eat gluten-rich foods, impairing the absorption of nutrients and sugars and causing excess gas to build up.
• Motility disorders, in which the contents of the gut do not move well through the gastrointestinal tract, can cause a sensation of bloating.
• H. pylori gastritis, a bacterial infection of the lining of your stomach, can cause bloating.
• Chronic inflammation of the pancreas can cause bloating due to fat malabsorption.
• Abdomino-phrenic dyssynergia (APD) is a rare condition in which your diaphragm and your abdominal muscles work out of sync, causing visible bloating without any gas build-up.

What does bloating feel like?

While everybody experiences this symptom differently, most patients describe it as an uncomfortable tightness or sensation of fullness in the abdomen. They feel swollen or even pregnant when they are not, and sometimes their clothing doesn’t fit right after eating.

Do any cancers have bloating as a symptom?

Yes. Ascites is a symptom of several gynecologic cancers, including:

• Ovarian cancer
• Fallopian tube cancer
• Endometrial cancer
• Primary peritoneal cancer

However, in these cases, the bloated sensation is due to the abnormal accumulation of fluid in the abdominal cavity, not gas in the digestive tract.

Rarely, a blockage in your gut can lead to fluid and gas build up anywhere along your gastrointestinal tract. If that happens, food and liquids may start backing up behind it, making you feel bloated, full and maybe even nauseated.

When should you see a doctor about bloating?

The general rule is to see a doctor for any symptom that lasts more than two weeks. But see one sooner if you start feeling abdominal pain or notice that you’ve lost weight without really trying.

And, see a doctor right away if you start having trouble swallowing or notice blood in your stool or vomit, have chronic diarrhea, or a family history of gastrointestinal cancer or inflammatory bowel disease.

How do you relieve bloating?

That depends on what’s causing it. Bloating is one of the top reasons people visit a gastroenterologist. Once we rule out more worrisome causes, we can manage symptoms to improve your quality of life.

• If we suspect a dietary intolerance, we may order testing and ask you to start keeping a food journal to identify possible triggers, then make recommendations to modify your diet.
• If we confirm an overgrowth of bacteria in the gut, we can prescribe an antibiotic to kill it.
• If the cause is constipation, we may consider laxatives and/or biofeedback therapy.
• If the cause is APD, we may prescribe physical therapy with a focus on diaphragmatic breathing.

Over-the-counter remedies like simethicone (an anti-foaming agent that breaks up gas bubbles) and laxatives (to relieve constipation) can be considered for minor relief. Other strategies, such as walking after meals, avoiding carbonated drinks, eating slowly and drinking peppermint tea, may also relieve symptoms.

But if you’re really concerned about bloating, you should see a gastroenterologist and have a complete workup done to determine its source.

Anusha Thomas, M.D., is a gastroenterologist at UT MD Anderson with a special interest in hepatology.

Request an appointment at UT MD Anderson online or call 1-877-632-6789.