Gas/Bloating

Bloating and distension are among the most common GI symptoms that people experience.

In collaboration with the National Institutes of Health, the MyGiHealth research team conducted a national survey and found that 34% of Americans reported having at least some bloating and 25% had some distension within the last 7 days.

Bloating and distension are especially common for people with:

  • Irritable bowel syndrome (IBS)

  • Constipation

  • Premenstrual syndrome (PMS)

Everyone has gas; people pass gas an average of 10 times per day, and some people may pass gas up to 20 times per day.

What is it?

Bloating is a very common GI symptom that can mean different things to different people. It’s important to understand the differences between bloating and distension. Here is the difference:

  • Bloating is the feeling of being too full. People may describe the feeling as “tightness” or “pressure” in the belly.

  • Distension is when the belly looks like it is larger than normal. People may describe distension as their belly looking “puffy”, “round”, “full”, or “pregnant”.

Both bloating and distension may occur because of too much gas inside the body. People can have too much gas when:

  • They swallow excessive air while eating or drinking

  • They drink too much carbonated (fizzy) drinks

  • Nutrients are broken down in the colon by bacteria inside your body, leading to gas formation

Your body handles intestinal gas in two basic ways:

  • The intestines absorb the gas into your system

  • Your body lets it out, as a burp (gas leaving the mouth) or flatulence (gas leaving the anus)

If your body makes too much gas, and if it cannot absorb or let out the gas fast enough, then you may feel bloated or become distended.

If you plan to see a doctor for bloating or distension, then it will be important to describe the symptoms you are experiencing. The “My History” function of MyGiHealth asks more about bloating and distension and can help you translate your symptoms into “doctor talk” should you plan to see a healthcare provider.

What causes it?

Bloating, distension, and gas can occur from a variety of causes, including:

  • Swallowing too much air

  • Producing too much gas

  • Gas moving slowly inside your body

  • Overeating

  • Having a period (menstruating)

Let’s explore each of these causes.

Swallowing too much air

We may swallow too much air when we:

  • Eat or drink quickly

  • Drink fizzy drinks like soda

  • Smoke

  • Chew gum that contains a sugar called sorbitol

  • Wear loose dentures

Producing too much gas

  • Certain foods cause the body to make more gas than normal. When these foods reach the colon, bacteria break them down and make gas.

  • Eating foods the body can't handle can cause gas:

    • Dairy products. Some people can't digest a sugar in dairy products. This is called lactose intolerance.

    • Fruit sugar. Some people can't break down the sugar found in fruit (called fructose).

    • Wheat. Some people can't break down wheat, rye, and barley because of a genetic condition called celiac disease. Others have symptoms when they eat wheat; we don’t fully understand why this occurs. These people have a "wheat intolerance."

  • Eat artificial sweeteners, such as sorbitol, xylitol, or mannitol can cause gas.

  • Foods high in fiber can cause gas.

Gas moving slowly

The body may take longer to let gas out. Then gas builds up and causes pain. Gas moves more slowly when people:

  • Have certain medical issues, like:

    • Slow stomach emptying (gastroparesis)

    • Constipation

    • Irritable bowel syndrome (IBS)

    • Too much bacteria in their small intestine

  • Take certain medicines

  • Eat high-fat foods

  • Lie down

  • Have muscles that don't relax to let gas move out

Pain from food, gas, or stool

Sometimes people may feel pain from normal amounts of gas, food, or stool. Medical issues can cause this, like:

  • Irritable Bowel Syndrome (IBS)

  • Functional dyspepsia (pain in the upper abdomen, a feeling of uncomfortable fullness after eating, and nausea)

  • Chronic (long-term) stress

Other causes

People may feel bloated or distended when they:

  • Overeat. Too much food in the belly can make it larger.

  • Have a period (menstruate). Bloating is common when a woman has her period, but the cause is unknown.

Highly fermentable foods are foods that aren't easily digested in the small intestine.

Instead, it's digested in the colon, which creates more gas. This causes bloating and distension.

Highly fermentable foods include:

  • Apples
  • Avocados
  • Beans
  • Beer and wine
  • Bread
  • Brussel sprouts
  • Cabbage (and sauerkraut)
  • Cheese
  • Cherries
  • Cured meats (like salami, pepperoni, or sausages)
  • Lentils
  • Milk
  • Mushrooms
  • Olives
  • Pears
  • Pickles
  • Vinegar
  • Soy Sauce
  • Yogurt

Caution: Here are some common medicines that cause bloating and distension:

Medicines to treat allergies or colds

  • Diphenhydramine (Benadryl©)
  • Hydroxyzine (Atarax©, Vistaril©)
  • Cyproheptadine (Periactin©)
  • Vitamins
  • Iron (Ferrous sulfate, Ferrous gluconate)
  • Aluminum
  • Calcium

Medicines to treat heart disease

  • Cardiovascular medicines
  • Furosemide (Lasix©)
  • Clevidipine (Cleviprex©)
  • Nifedipine (Adalat©, Procardia©)
  • Medicines to treat diarrhea
  • Diphenoxylate/atropine (Lomotil©)
  • Loperamide (Immodium©)

Medicines to treat ulcers

  • Cimetidine (Tagamet©)
  • Ranitidine (Zantac©)
  • Medicines to treat mental health outcomes
  • Amitriptyline (Elavil©)
  • Chlordiazepoxide (Librium©)
  • Nortriptyline (Pamelor©)

Medicines to treat bladder conditions

  • Oxybutynin (Ditropan©)
  • Solifenacin (Vesicare©)
  • Tolterodine (Detrol©)

Medicines to treat pain

  • Codeine
  • Fentanyl
  • Hydrocodone
  • Hydromorphone
  • Methadone
  • Morphine
  • Oxycodone
  • Tramadol
  • Herbal medicine
  • St. John's Wort

To find out if your medicines might cause bloating or distension, talk to your doctor or pharmacist.

The pelvic floor muscles and anal sphincter don't relax the way they should. This issue is called dyssynergia.

How do I manage it?

Swallow Less Air

Bloating is often caused by swallowing air. To swallow less air:

  • avoid chewing gum
  • don't drink fizzy drinks and alcohol
  • avoid sucking on hard candy
  • eat more slowly
  • quit smoking or smoke less

Limit or Avoid Foods that Make Extra Gas

Some foods are not digested completely in the small intestine. These sugars move to the colon, where they are digested by bacteria. These bacteria release a lot of gas.

Limit or avoid these types of foods to help reduce gas:

  • Beans
  • Cabbage
  • Broccoli
  • Cauliflower
  • Brussels sprouts
  • Bran
  • Other types of fiber
  • Sugar-free candy or gum
  • Other highly fermentable foods

Limit or Avoid Dairy Products

People who don't have enough lactase in their intestines cannot break down lactose and cannot absorb this sugar. Some of these people will become bloated and may need to avoid eating or drinking dairy products.

  • Lactase is an enzyme that helps digest lactose.
  • Lactose is a sugar found in milk and other dairy products.
  • If lactose is not digested in the small intestine, it moves into the colon.
  • In the colon, bacteria digest the sugar (lactose), where it ferments, which causes gas and bloating.

Limit or Avoid Fructose (Sugar)

  • Fructose is a type of sugar found in fruits and many sweet processed foods.

  • Fructose is easier to absorb in the small intestine when you eat foods that have both fructose and glucose in them.

  • Foods and drinks that contain lots of fructose and little or no glucose are harder for the body to digest.

  • Fructose that is not absorbed in the small intestine moves to the colon. In the colon, bacteria digest the sugar, where it ferments, which causes gas and bloating.

  • Avoiding food and drink that have mostly fructose may help with gas and bloating.

Avoid Artificial sweeteners

  • Some artificial sweeteners, like sorbitol, are also poorly digested in the small intestine. This means they are absorbed in the colon, causing gas and bloating.

  • Many sugar-free candies and gums contain these sweeteners.

  • Avoiding foods with these artificial sweeteners may help reduce gas and bloating.

Limit Fiber

Eating fiber is healthy, but sometimes fiber may cause gas or bloating. You can get fiber from food or you can take it as a supplement.

  • Adding fiber to your diet slowly may help reduce bloating.

  • Most people's bodies get used to digesting more fiber within 3 weeks. By that time, feelings of bloating and gas may improve.

  • There are different types of fiber. People may react differently to each type. It may be helpful to try out different types of fiber to see how they work for you.

To reduce or relieve gas and bloating:

  • Eat and drink slowly

  • Don’t smoke

  • Make sure dentures fit well

  • Do breathing exercises to reduce air swallowing

  • Walk, jog, and stretch to help food move through the digestive system and out of the body more quickly.

  • Lie down on your right side (not left side). When you have gas trapped inside your colon, it can sometimes come out more easily when you lie on your right.

Some medications may help to relieve gas, but are believed to not work very well.

Simethicone

Simethicone dissolves small gas bubbles in the stomach and intestines.

Most people start with small doses, but may need up to 125mg with meals to see a difference.

Some antacids contain simethicone and may help with bloating. Antacids without simethicone won't help with bloating.

Common names:

  • Gas-X™
  • Mylicon™
  • Maalox Anti-Gas™
  • Mylanta Gas™
  • Maalox Plus™

Activated Charcoal

There are two ways to use activated charcoal:

  1. Take an activated charcoal tablet
  2. Wear underwear lined with activated charcoal

Activated charcoal tablets or capsules may help:

  • Reduce the amount of gas
  • Decrease the odor from gas

Charcoal-lined undergarments are available and may help reduce odor, but won't reduce the amount of gas. They are available online.

Digestive enzymes

The body has enzymes that help the body break down food during digestion. You can also take enzymes to help your body digest certain foods.

For people with low pancreatic enzymes, these supplements can help with digestion and reduce gas and bloating. However, for a person with a normal pancreas, taking these enzymes will probably not help with gas or bloating.

Common names:

  • Beano™
  • Vitacost Gas Enzyme™
  • Bean-zyme™
  • Vegan-zyme™

Alpha-galactosidase

Alpha-galactosidase helps break down complex sugars in foods like beans or certain vegetables that can cause gas and bloating.

Taking alpha-galactosidase when eating these foods may help reduce gas and bloating.

Probiotics

Probiotics are bacteria that can improve health if people take enough. We don't know exactly how probiotics might help with gas and bloating. But, some research shows certain probiotics may help by:

  • Creating the right amounts of healthy bacteria in the digestive system. Probiotics are often called "friendly bacteria".
  • Decreasing the amount of bacteria the colon has to break down, so less gas is made
  • Helping the colon contract more and move gas through faster, which means less bloating

Common names:

  • Align™
  • Activia™
  • VSL #3™

Bran is poorly digested and adds bulk to stool. It is also broken down by bacteria in the colon, which produces a lot of gas. This is why bran helps with constipation, but it can also make bloating worse.

Fiber can help with constipation. Improving constipation can sometimes help with bloating. However, taking too much fiber can sometimes cause bloating.

Highly fermentable foods are foods that aren't easily digested in the small intestine.

Instead, these foods are digested in the colon, which creates more gas. This can cause bloating and distension.

Highly fermentable foods include:

  • Apples
  • Avocados
  • Beer and wine
  • Bread
  • Cheese
  • Cherries
  • Cured meats (like salami, pepperoni, or sausages)
  • Lentils
  • Milk
  • Mushrooms
  • Olives
  • Pears
  • Pickles
  • Vinegar
  • Soy Sauce
  • Yogurt
  • And many more

Foods that have at least as much glucose as they do fructose may cause less bloating than foods with high fructose and low glucose. It may be helpful to avoid foods like these:

  • Foods containing high fructose corn syrup
  • Fruit juices
  • Apples, applesauce, apple juice
  • Melons
  • Artichokes
  • Mangoes
  • Pears
  • Fizzy drinks (sodas)
  • Fresh, dried, and processed fruit (not including bananas and citrus fruits)
  • Honey
  • Maple syrup
  • Molasses
  • Agave nectar
  • Sweet wines
  • Certain vegetables (asparagus, beans, broccoli, cabbage, leeks, onions, zucchini)

Everyone is different. Some people are able to tolerate small amounts of these foods while others are not. It may be helpful to experiment until you find the right balance.

  • Aspartame
  • Mannitol
  • Saccharin
  • Sorbitol
  • Sucralose
  • Xylitol

There are some foods and drinks that contain artificial sweeteners that may be surprising. Some of those foods are:

  • Certain breakfast cereals
  • Foods that are labeled "diet" or "sugar-free' (like candy, popcorn, pudding, jello)
  • Certain yogurts
  • Light or diet sodas and fruit juices
  • Certain protein or snack bars

To avoid artificial sweeteners, read the nutrition labels on food and drink products. Aspartame, acesulfame, sorbitol, xylitol, saccharin, and sucralose are common artificial sweeteners that are added to foods.

There are some foods and drinks that contain artificial sweeteners that may be surprising. Some of those foods are:

  • Certain breakfast cereals
  • Foods that are labeled "diet" or "sugar-free' (like candy, popcorn, pudding, jello)
  • Certain yogurts
  • Light or diet sodas and fruit juices
  • Certain protein or snack bars

To avoid artificial sweeteners, read the nutrition labels on food and drink products. Aspartame, acesulfame, sorbitol, xylitol, saccharin, and sucralose are common artificial sweeteners that are added to foods.

There are two kinds of fiber: soluble and insoluble.

Soluble fiber

Research studies show that eating foods high in soluble fiber can help with constipation. However, eating soluble fiber may cause gas and bloating.

You can get soluble fiber from foods:

  • Apples
  • Beans
  • Carrots
  • Lentils
  • Oatmeal
  • Oat cereal
  • Oranges
  • Peas
  • Tomatoes
  • Strawberries

and suplements:

  • Citrucel™
  • Benefiber™
  • Fiberchoice™
  • Fibercon™
  • Metamucil™

Insoluble fiber

There's less information about whether insoluble fiber can help with constipation. Insoluble fiber may cause less gas and bloating than soluble fiber.

You can get insoluble fiber from foods:

  • Barley
  • Broccoli
  • Cabbage
  • Celery
  • Leafy vegetables
  • Nuts
  • Seeds
  • Tomatoes
  • Whole grains
  • Whole wheat

and suplements:

  • Citrucel™
  • Normacol™
  • Normafibe™

Everyone is different. Most people find it helpful to try different kinds of fiber until they find something that works for them. Please be mindful of your own dietary needs when choosing foods to try. These foods are examples and may not work for everyone.

People may have low pancreatic enzymes if they have:

  • Acute or chronic pancreatitis
  • Surgical removal of the pancreas
  • Pancreatic cancer
  • Cystic fibrosis
  • Stomach ulcers
  • Crohn's disease
  • Autoimmune disorder
  • Obstruction due to a gall stone
  • Diabetes for many years

Where can I learn more?

To learn more about gas and bloating, please visit these websites: