What is flatulence

Flatulence is the passage of excess gastrointestinal air and gas from the back passage (anus). In colloquial terms this is called ‘farting.’ Everyone has gas. Most people pass gas (fart) 13 to 21 times a day. Passing gas through the mouth is called belching or burping. Most of the time gas does not have an odor. The odor comes from bacteria in the large intestine that release small amounts of gases that contain sulfur.

Flatulence is usually nothing to worry about. Everyone farts, some people more than others. What’s normal is different for everyone. If you notice a change or it’s affecting your life, there are things you can do.

Sources of Intestinal Gas

Gas in the digestive tract (the esophagus, stomach, small intestine, and large intestine) comes from two sources:

• air that you swallow and
• the normal breakdown of certain undigested foods by harmless bacteria that are naturally present in the large intestine.

Certain foods may cause gas. Foods that produce gas in one person may not cause gas in another.

Swallowed Air – Air swallowing (aerophagia) is a common cause of gas in the stomach. Everyone swallows small amounts of air when eating and drinking. However, eating or drinking rapidly, talking while eating, chewing gum, smoking, or wearing loose dentures can cause some people to take in more air.

Burping, or belching, is the way most swallowed air leaves the stomach. The remaining gas moves into the small intestine where it is partially absorbed. A small amount travels into the large intestine for release through the rectum. (The stomach also releases carbon dioxide when stomach acid and bicarbonate mix, but most of this gas is absorbed into the bloodstream and does not enter the large intestine.)

Bacteria – Gases are produced as a by-product when certain food materials are digested by naturally occurring bacteria in the large intestine, or colon. These bacteria are responsible for digesting materials like complex carbohydrates (sugar, starches, and fiber found in many foods) and cellulose, which are not normally digested in the upper gastrointestinal tract.

The quantity and mixture of gases depend on the types of bacteria in the colon; everyone has a unique assortment of bacteria from the time of birth. These gases include hydrogen, carbon dioxide, and, in some people methane. Trace gases, such as hydrogen sulfide, are responsible for the odor. Foods that produce gas in one person may not cause gas in another.

You can reduce the amount of flatulence gas you have by:

• Drinking lots of water and non-fizzy drinks
• Eating more slowly so you swallow less air when you eat
• Avoiding milk products if you have lactose intolerance

Things you can do to cut down excessive or smelly flatulence

DO

• eat smaller meals, more often
• drink or chew food slowly
• exercise to improve how your body digests food
• eat a healthy, balanced diet
• try to drink peppermint tea

AVOID

• chew gum, smoke, or suck pen tops or hard sweets to avoid swallowing air
• wear loose-fitting dentures
• eat too many foods that are difficult to digest and make you fart

Foods that are more likely to form gas and cause flatulence include:

• Milk, dairy products, and medications that contain lactose–If your body doesn’t produce the enzyme (lactase) to break it down.
• Certain starches–wheat, oats, corn, potatoes. Rice is a good substitute.
• Alcohol may impair intestinal digestion so that more food is available for gas production.
• Foods that are difficult to digest:
  • cabbage
  • broccoli
  • cauliflower
  • brussels sprouts
  • pulses, like beans (baked beans) or lentils
  • dried fruit, like raisins or apricots
  • onions
  • food or drinks containing the sweetener sorbitol

Foods less likely to cause gas include:

• Meat, poultry, fish
• Eggs
• Vegetables such as lettuce, tomatoes, zucchini, okra,
• Fruits such as cantaloupe, grapes, berries, cherries, avocado, olives
• Carbohydrates such as gluten-free bread, rice bread, rice

Medicines can help reduce gas or the pain and bloating caused by gas. A pharmacist can help with excessive or smelly flatulence for example, charcoal tablets or special underwear and pads that absorb smells. Products containing chlorophyllin copper (e.g., Nullo, Derifil) can help minimize offending odor. Chlorophyllin copper (e.g., Nullo, Derifil) has been used to decrease odor in patients with colostomies or who were incontinent of urine or feces. Digestive enzymes, such as lactase supplements, actually help digest carbohydrates and may allow people to eat foods that normally cause gas.

If your symptoms still bother you, see your health care provider.

Key facts

• Belching and flatulence are normal body processes.
• Gas comes from two main sources: swallowed air and normal breakdown of certain foods by harmless bacteria naturally present in the large intestine.
• Swallowed air is “gas” in the body and contributes significantly to symptoms.
• Swallowed air can be affected by a number of contributing factors. Dentures that do not fit well can cause people to swallow more saliva which carries air bubbles; postnasal drip tends to make people swallow more often, carrying more air to the stomach; smoking a cigar or pipe may increase the amount of saliva produced and swallowed; eating too fast increases the amount of air swallowed; gum chewing and sucking on hard candies also increases the amount of air swallowed.
• Many foods with carbohydrates can cause gas. Fats and proteins cause little gas.
• The amount of gas caused by certain foods varies from person to person. Effective dietary changes depend on learning through trial and error how much of the offending foods one can handle. For one week try eliminating foods or beverages in your diet that you suspect most likely are causing you gas or odor problems. Then gradually reintroduce them one at a time to help identify the offenders.
• Unabsorbed dietary carbohydrates can cause gas production by colon bacteria.
• Carbonated beverages, sucking on hard candy, and chewing gum should be avoided.
• Abdominal distension when erect but not recumbent may be due to weak abdominal muscles.
• Increasing frequency or severity of symptoms should prompt medical attention.

What causes flatulence

When you break down and digest food in your intestines, some gases are created – that is normal.

You swallow air during the process of eating. Individuals can have excess swallowing due to sucking on hard candies or chewing gum. Drinking carbonated beverages such as soda or beer can also generate excess gastric air. In addition, individuals who experience anxiety may swallow air excessively. Poorly fitting dentures and chronic postnasal “drip” can also cause excess air swallowing. As a result, significant amounts of gas can enter the stomach and small bowel in 24 hours which can lead to belching, bloating or flatulence.

Some carbohydrates cannot be digested by the enzymes in the small intestine and reach the colon where bacteria metabolize them to hydrogen and carbon dioxide gasses. Examples of such food are bran, cabbage, cauliflower, broccoli, and beans. This can result in excess flatulence in some patients. Many patients experience abdominal cramps, bloating and flatulence when they ingest milk, certain cheeses or ice cream because they lack the enzyme (lactase) which is required to digest milk sugars (lactose). This condition, called lactose intolerance, is less common in people of northern European origin.

Another cause of bloating and abdominal distension is termed bacterial overgrowth. This is not an infection, but occurs when there is an excess amount of normal bacteria in the small intestine. This results in increased production of intestinal gas contributing to the above symptoms. Finally, underlying constipation may also contribute to bloating and a sense of abdominal distention.

However, the amount of wind you create is influenced by what you eat and drink. Excessive or smelly flatulence can be caused by you swallowing air or eating foods that are difficult to digest.

Several high-fiber foods, carbonated drinks and artificial sweeteners can cause excessive flatulence. Excessive or smelly flatulence can also be caused by:

• fresh and dried fruits, such as apples, pears and raisins
• nuts and seeds
• beans and peas and some other vegetables
• eating dairy if you have lactose intolerance
• medical conditions like irritable bowel syndrome (IBS)
• medications such as cholestyramine and orlistat
• swallowing air if you are anxious, or if you eat quickly, smoke or chew gum.

Excessive or smelly flatulence can also sometimes be a sign of a health condition.

Don’t self-diagnose – see a doctor if you’re worried about flatulence.

Excessive or smelly flatulence can also be a side effect of some medicines, including:

• non-steroidal anti-inflammatory drugs (NSAIDS), like ibuprofen
• some laxatives
• antifungal medicines
• statins

Don’t stop or change your medication without speaking to your doctor first.

Risk factors for excessive flatulence

As mentioned above, excessive air swallowing, and certain foods and carbonated beverages are significant contributors to belching and flatulence. Some patients with Irritable Bowel Syndrome (IBS) appear to be uniquely sensitive to normal or only slightly increased volumes of intestinal gas and may develop abdominal cramps as a result. Patients with altered anatomy due to surgery or those with certain rheumatologic diseases may be at an increased risk of bacterial overgrowth in the small intestine which can lead to belching, bloating or flatulence.

Some patients, particularly women who have had one or more pregnancies, experience abdominal distension when standing erect. This is often assumed to be gas accumulation. However, if the distension is not present when the patient is lying “flat”, then the likely explanation is weak abdominal muscles (which extend from the lower rib cage to the pelvis on both sides of the umbilicus) due to the stretching and loss of muscle tone which occurs during pregnancy.

Foods that may cause flatulence

Most foods that contain carbohydrates can cause gas. By contrast, fats and proteins cause little gas (although certain proteins may intensify the odor of gas).

Foods more likely to cause gas include:

• Beans (Presoaking reduces the gas-producing potential of beans if you discard the soaking water and cook using fresh water)
• Vegetables such as artichokes, asparagus, broccoli, cabbage, Brussels sprouts, cauliflower, cucumbers, green peppers, onions, radishes, celery, carrots
• Fruits such as apples, peaches, raisins, bananas, apricots, prune juice, pears
• Whole grains and bran (Adding them slowly to your diet can help reduce gas forming potential)
• Carbonated drinks (Allowing carbonated drinks, which contain a great deal of gas, to stand open for several hours allows the carbonation/gas to escape)
• Milk and milk products, such as cheese and ice cream
• Packaged foods prepared with lactose, such as bread, cereal, and salad dressing
• Foods containing sorbitol, such as dietetic foods and sugarfree candies and gums
• Beverages such as wine and dark beer

Odor forming foods may include:

• alcohol,
• asparagus,
• beans,
• cabbage,
• chicken,
• coffee,
• cucumbers,
• dairy products,
• eggs,
• fish,
• garlic,
• nuts,
• onions,
• prunes,
• radishes, and
• highly seasoned foods.

Sugars

The sugars that cause gas are raffinose, lactose, fructose, and sorbitol.

• Raffinose — Beans contain large amounts of this complex sugar. Smaller amounts are found in cabbage, Brussels sprouts, broccoli, asparagus, other vegetables, and whole grains.
• Lactose — Lactose is the natural sugar in milk. It is also found in milk products, such as cheese and ice cream, and processed foods, such as bread, cereal, and salad dressing. Many people, particularly those of African, Native American, or Asian background, have low levels of the enzyme lactase needed to digest lactose. Also, as people age, their enzyme levels decrease. As a result, over time people may experience increasing amounts of gas after eating food containing lactose.
• Fructose — Fructose is naturally present in onions, artichokes, pears, and wheat. It is also used as a sweetener in some soft drinks and fruit drinks.
• Sorbitol — Sorbitol is a sugar found naturally in fruits, including apples, pears, peaches, and prunes. It is also used as an artificial sweetener in many dietetic foods and sugar free candies and gums.

Starches

Most starches, including potatoes, corn, noodles, and wheat, produce gas as they are broken down in the large intestine. Rice is the only starch that does not cause gas.

Fiber

Dietary fiber is carbohydrate that is indigestible in the small intestine and reaches the colon relatively intact. In the colon, certain bacteria digest fiber (fermentation), which produces gas. Dietary fiber can be classified as either soluble or insoluble.

Soluble fiber dissolves in water and becomes a soft gel. It is found in oat bran, beans, barley, nuts, seeds, lentils, peas, and most fruits. Insoluble fiber does not dissolve or gel in water. It absorbs liquid and adds bulk to stool. Cellulose (found in legumes, seeds, root vegetables, and vegetables in the cabbage family), wheat bran, and corn bran are examples of insoluble fiber.

High fiber substances containing both soluble and insoluble fibers have the properties of both. They include oat bran, psyllium, and soy fiber. Methylcellulose is a semi-synthetic fiber. It is soluble and gel forming, but not fermentable.

Types of fiber differ in the speed and extent to which they are digested in the gastrointestinal (GI) tract, and in the process of fermentation. The solubility and fermentation of a particular fiber affects how it is handled in the gastrointestinal (GI) tract. However, the effect of identical fibers varies from person to person.

A gradual increase in dietary fiber can modify and improve symptoms. But individual responses vary and too much of a type of fiber can worsen symptoms. It may be necessary to try different types of fiber. With any dietary fiber it is best to start low and go slow.

Symptoms that accompany flatulence

There are usually no symptoms when flatulence is at a normal level. You might not even notice when you pass wind for much of the time. But if you have excessive flatulence, you might:

• break wind more often
• have pain, bloating or rumbling in the abdomen
• notice that your farts are loud and smelly.

Flatulence treatment

There is no simple dietary solution to excessive flatulence since foods affect people’s digestion differently. A useful approach is to work out which foods seem to cause the problem in your case and either to avoid them altogether or to cut back how much you consume. But be aware that high-fiber foods form part of a healthy diet.

Foods such as cauliflower, broccoli, cabbage, beans, and bran should be avoided. Milk and other dairy foods should be avoided. Lactaid milk or non-dairy milk such as soy or almond milk can be used. Chewing gum and sucking on hard candies should be avoided. Sugar free gum and hard candies should be avoided as they may have mannitol or sorbitol as sweeteners which can cause flatulence.

• To ensure that only potentially symptom causing foods are eliminated without resulting in marked dietary restrictions, you should eliminate food items one by one and keep a symptom diary.
• Try monitoring your diet (time of day and description of foods eaten and drinks ingested, and times of each episode of gas) for a week or so to identify what may cause increased gas production or what may effect odor.

You can also decrease flatulence by avoiding chewing gum, fizzy drinks such as soda and beer, foods with artificial sweeteners and smoking. Relaxing when you eat and eating slowly can also help.

You could discuss with your doctor or pharmacist whether to take over-the-counter antacids or activated charcoal tablets. This may benefit some people.

Simethicone (e.g., Gas-X, Mylanta Gas, Phazyme) is a foaming agent that joins gas bubbles in the stomach so that gas is more easily belched away have been promoted as treatment for gaseousness, but their efficacy has not been convincing.

Charcoal tablets have also been used to reduce flatulence without convincing benefit. Bismuth subsalicylate has been used to reduce the noxious odor of some sulfa-containing rectal gasses.

Alpha-d-galactosidase (e.g., Beano, Gas-X Prevention), an over the counter product, contains the sugar-digesting enzyme that the body lacks to digest the sugar in beans and many vegetables, has been used to help in the digestion of complex carbohydrates. The enzyme comes in liquid or tablet form. Alpha-d-galactosidase (e.g., Beano, Gas-X Prevention) has no effect on gas caused by lactose or fiber. Heat degrades the enzyme in alpha-d-galactosidase (e.g., Beano, Gas-X Prevention) so it cannot be added to food while it is being cooked. Some patients may benefit from this strategy. Beano is made from an enzyme (alpha-galactosidase) extracted from a food-grade mold; if you are allergic to molds you may react to Beano. Those with galactosemia (an inherited disorder characterized by the inability to metabolize galactose) should not use Beano without first consulting their physician.

Digestive enzymes, such as lactase supplements, actually help digest carbohydrates and may allow people to eat foods that normally cause gas. The enzyme lactase, which aids with lactose digestion, is available in liquid and tablet form without a prescription (e.g., Dairy Ease, Lactaid). Adding a few drops of liquid lactase to milk before drinking it or chewing lactase tablets just before eating helps digest foods that contain lactose. Also, lactose-reduced milk and other products are available at many grocery stores.

Products containing chlorophyllin copper (e.g., Nullo, Derifil) can help minimize offending odor. Chlorophyllin copper (e.g., Nullo, Derifil) has been used to decrease odor in patients with colostomies or who were incontinent of urine or feces. Chlorophyllin is very closely related to chlorophyll, the green pigment found in most plants that converts the sun’s energy and carbon dioxide to sugar and oxygen. Without chlorophyll there would be no oxygen, no food, no people and no incontinence. By adding sodium and copper to chlorophyll the pigment can be dissolved in water and becomes chlorophyllin. There is very little solid scientific evidence of chlorophyllin effectiveness, In the absence of such needed scientific proof, it can at least be said that chlorophyllin, taken as a tablet, has been extensively used in the past for the treatment of fecal and urinary odor. Urine and feces will turn green. Green pigment in clothing is extremely hard to wash out (like grass stains). Aside from that, there seems little if any evidence that chlorophyllin can cause any harm.

Individuals with Irritable Bowel Syndrome (IBS) may benefit from symptomatic therapy for “gas pains” by using antispasmodic therapy such as dicyclomine or hyoscyamine under the tongue.

Some patients with bacterial overgrowth may see improvement from the occasional use of antibiotics to reduce the number of bacteria in the small bowel, thereby reducing gas production.

If weak abdominal muscles are suspected as a cause for abdominal distension, abdominal-tensing exercises may be helpful, although very difficult to achieve when patients are middle aged and older.

If symptoms fail to respond to the dietary strategies noted above, medical help should be sought to be confident that no other underlying abnormalities are present.