Abdominal bloating occurs when the gastrointestinal (GI) tract is filled with air or gas. Most people describe bloating as feeling full, tight, or swollen in the abdomen. Your abdomen may also be swollen (distended), hard, and painful. Bloating is often accompanied by:
- excessive gas (flatulence)
- frequent burping or belching
- abdominal rumbling or gurgles
Abdominal bloating can interfere with your ability to work and participate in social or recreational activities. Bloating is common among both adults and children.
Abdominal bloating can be alarming, particularly when it is very painful. Some people notice that their belly looks swollen or misshapen, or they may experience sharp abdominal pain. Yet in many cases, the cause may be something as simple as indigestion or too much gas building up in the stomach and bowels.
What Is Bloating?
Bloating is distention (protrusion) of the abdomen, often accompanied by an uncomfortable feeling of fullness or tightness. Although it can cause your stomach to appear larger than normal and your clothing to feel tight around your waist, bloating is not caused by excess abdominal fat. Most often it occurs after eating a large meal, but also is associated with gluten intolerance, the build-up of digestive gasses, or, if you menstruate, the accumulation of fluid during your period. Effectively preventing or relieving belly bloat depends on what causes it. It often can be prevented by measures such as changing eating habits or taking medication to prevent or relieve gas.
When our stomach is empty, it is about the size of a clenched fist. However, the design and structure of the stomach allows it to increase in shape and size to accommodate what we eat. That said, it’s worth bearing in mind that your stomach can only handle about a litre to a litre and a half of food at any one time. Overeating can put strain on your stomach and compromise your digestion.
Most often bloating is linked to eating habits or certain foods and beverages that cause the build-up of gasses in the digestive system—among them, carbon dioxide, oxygen, nitrogen, hydrogen, and sometimes methane or sulfur (which is responsible for the unpleasant odor when gas is released).
Food-related causes of bloating include:
- Eating too much: Stomach tissue is stretchy: If you put more into it than it can easily accommodate it will stretch enough to protrude.
- Eating too fast: Consuming food without taking a break doesn’t give your belly and your brain time to acknowledge the signs of (satiety) fullness. By the time your body catches up, 15 or 20 minutes after you’ve eaten, you may feel as if you’ve downed two or three meals rather than one.
- High-fiber foods: Whole grains and other foods that are rich in fiber can cause bloating, especially if you aren’t used to eating them.
- Constipation. Stool backed up in the bowels can cause distention of the lower abdomen.
- Swallowing air: When you chew gum or drink carbonated beverages, you’re essentially consuming air. The same holds for drinking from a straw.
- Drinking: Alcohol of any type may cause temporary puffiness by irritating the lining of the stomach. Bubbly beverages (beer, champagne, cocktails mixed with soda) can be especially problematic.2 People who abuse alcohol may develop a condition called alcoholic gastritis—inflammation that tends to flare after a binge, causing bloating and other symptoms.3
- Lactose intolerance: People who are lactose intolerant do not have lactase, the enzyme needed to digest the sugar in dairy products, and as a result experience nausea and bloating within 30 minutes to 2 hours after consuming foods such as milk or cheese.
- Gluten: Some people who are sensitive to gluten (a protein found in wheat and other grains) or who have celiac disease may experience gas and bloating after eating foods with gluten.
- Irritable bowel syndrome (IBS): Some foods, such as artificial sweeteners, certain fruits and vegetables, and or dairy products may produce uncomfortable gas and discomfort in some people.
The hormonal fluctuations that occur during menstruation can affect fluid levels in the body. Bloating is common during a person’s period and is a key symptom of premenstrual syndrome.
Ovarian cancer bloating is due to a buildup of fluid (called ascites) in your abdomen and can also come with pain. Most of the fluid is formed from cancer cells, but it can also be the result of blockages in the lymphatic drainage system or intestinal blockages caused by the presence of cancer, says Lauren Cobb, MD, assistant professor of gynecologic, oncologic, and reproductive medicine at the University of Texas MD Anderson Cancer Center.
Painful bloating could also signal a bowel obstruction, a blockage in the small or large intestine that stops food from passing through.
Bloating that doesn’t go away
For bloating to be potentially worrisome, it generally needs to have lasted for more than two weeks in a month, says Monique Swain, MD, an obstetrician and gynecologist at Henry Ford Health System in Detroit.
If bloating doesn’t go away after making simple diet swaps or going to the bathroom, speak up. “If bloating is persistent and does not vary with changing eating habits or bowel movements, it is a good idea to seek medical care,” adds Alex Hewlett, DO, associate professor of medicine at the University of Nebraska Medical Center.
Changes in bathroom habits
Another clue that bloating could be a sign of ovarian cancer is a change in your bathroom behavior. Out-of-the-ordinary bowel or urinary issues can be a tip something is wrong.
For example, you might suddenly need to go to the bathroom more urgently “if a mass is big enough and pressing on the bladder,” says Dr. Swain.
Bloating can also be a sign of other cancers, like breast, pancreatic, colon, and stomach cancer, if the cancer appears along the lining of the abdominal cavity, says Dr. Cobb.
Large masses that take up a lot of space in the abdominal area can lead to changes in appetite, like feeling full very quickly or not wanting to eat. Some people with bloating due to cancer also experience nausea and vomiting.
Liver disease–which can be caused by alcohol use, hepatitis C, cancer, and more–can also lead to bloating and fluid buildup.
“Normally, this is a slow, insidious process where you just start to feel it in the lower belly,” Dr. Hewlett says. “As it progresses, your belly becomes more and more distended with fluid.”
If your bloating is due to liver disease, you might also feel tired, bruise easily, or develop jaundice, a yellowish tinge to the skin and eyes. “Seek medical care if there are other symptoms associated with bloating like these,” Dr. Hewlett adds.
Congestive heart failure can also result in bloating, not just in the abdomen but with swelling in the legs too.
In both heart failure and liver disease, bloating is usually a later symptom of the condition. “Once you get bloating and fluid retention, it may mean the disease process affecting your liver or heart is advanced,” says Dr. Hewlett. It’s important to speak up about your symptoms sooner rather than later.
Treatments And Home Remedies
Bloating can usually be safely treated at home. Some options that may help include:
- over-the-counter medications, including antacids or bismuth salicylate (Pepto-Bismol)
- applying a heat pad to the stomach
- drinking water
- eating peppermint
- drinking carbonated water
- taking a laxative to relieve constipation
Keeping a food diary to monitor bloating can also be useful. This can help with diagnosing food intolerances and making healthy lifestyle changes. Many people find that simply avoiding certain foods can prevent bloating and other gastrointestinal health issues.
How to Prevent Bloating
Typically, the first line of treatment for preventing gas and bloating is changing your diet. Research has shown that a low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet can reduce the symptoms of gas and IBS. A low FODMAP diet avoids fermentable, gas-producing food ingredients, such as:
Oligosaccharides, which are found in wheat, onions, garlic, legumes and beans
Disaccharides, such as lactose in milk, yogurt and ice cream
Monosaccharides, including fructose (a type of sugar found in honey), apples and pears
Polyols or sugar alcohols found in foods such as apricots, nectarines, plums and cauliflower, as well as many chewing gums and candies
“The small intestine doesn’t always fully absorb these carbohydrates, instead passing them to the colon, where they are fermented by bacteria and produce gas,” Lee says. Not everyone gets gas and bloating from every FODMAP foods. You might start by cutting out FODMAP foods and then slowly bringing them back into your diet one at a time to pinpoint problem foods.
In the long run, the key to preventing bloating is understanding its cause. If mild constipation is the problem, a fiber-rich diet, water and exercise may help, but these steps won’t always work for chronic constipation. Chronic constipation and other conditions, such as IBS or gastroparesis, require medical treatment, so it’s important to talk to your doctor about your bloating symptoms.