Everyone produces gas in their digestive tract and eliminates it either through the mouth (belching) or the rectum (flatulence). The average person produces between one and four pints of gas per day, and passes it about 14 times per day. Gas is made up mostly of odorless vapors such as carbon dioxide, hydrogen, nitrogen, oxygen, and occasionally methane.

Gas in the digestive tract is caused either by swallowing air (aerophagia) or from the breakdown of undigested foods by bacteria in the colon. Foods that cause gas in one person may not produce it in another. This is because common bacteria in the large intestine can eliminate the hydrogen that another type of bacteria produces. It’s a delicate balance, and researchers believe that it’s differences in this balance among individuals that cause some people to produce more gas than others.

Acid Reflux

Gastroesophageal reflux disease (GERD)—also known as acid reflex disease— affects between 10 and 20 percent of the population in Western countries such as the United States. It’s a more serious form of the common condition known as gastroesophageal reflux (GER). GER occurs when the lower esophageal sphincter (a ring of muscles located in the esophagus that works as a valve between the esophagus and stomach) either opens spontaneously or doesn't close properly. This malfunction allows the contents of the stomach to ascend into the esophagus. Digestive juices rise up with the food, causing the most common symptom: a frequent, burning pain known as acid indigestion or heartburn located in the middle abdomen.

You’re considered to have GERD when reflux symptoms are persistent and chronic, occurring more than twice per week. People of all ages may suffer from GERD, although it’s most likely to occur in those between the ages of 60 and 70. Over 23 million Americans report experiencing acid reflux every day.

Foods That Cause Gas

Most foods are broken down in the small intestine, but certain types—especially carbohydrates—may not be broken down. This can be due to a lack or absence of certain enzymes that aid in digestion. Undigested food moves from the small intestine to the colon, where it’s worked on by harmless bacteria. The unpleasant smell associated with flatulence is caused by sulfurous gases released by these bacteria. Foods that are notorious gas producers include:

  • apples
  • asparagus
  • beans (especially baked beans)
  • broccoli
  • Brussels sprouts
  • cabbage
  • carbonated beverages
  • cauliflower
  • chewing gum and hard candy
  • lettuces
  • peaches
  • pears
  • some whole grains

Causes of Acid Reflux

It’s unclear why some people develop acid reflux while others don’t. The lower esophageal sphincter (LES) of a person with GER relaxes in an otherwise healthy esophagus. One of the main causes appears to be the presence of a hiatal hernia. This allows the upper part of the stomach and the LES to move above the diaphragm (the wall of muscle that separates the stomach from the chest). A hiatal hernia typically produces no symptoms and is often found in healthy people over 50. Other factors that make acid reflux more likely are:

  • alcohol consumption
  • obesity
  • pregnancy
  • scleroderma (a connective tissue disease)
  • smoking

 Several medications can contribute to acid reflux as well, including:

  • anticholinergics (used for seasickness)
  • beta blockers (used for high blood pressure and heart disease)
  • bronchodilators (used for asthma)
  • calcium channel blockers (used for high blood pressure)
  • dopamine-active drugs (used for Parkinson's disease)
  • progestin (birth control)
  • sedatives (used for anxiety or insomnia)
  • tricyclic antidepressants

The Acid Reflux and Gas Connection

So, can acid reflux cause gas? The short answer is maybe. Many of the same things that contribute to gas also cause acid reflux. Making lifestyle changes to treat acid reflux may also help reduce excessive gas. For instance, you can eliminate carbonated beverages like beer to help relieve symptoms of acid reflux. Eating smaller meals more often may reduce the symptoms of both conditions, too.

The reverse also can be true—attempting to release gas may trigger acid reflux. Belching both during and after meals to release air when the stomach is full is normal. However, some people belch frequently and swallow too much air, releasing it before it enters the stomach. Many people mistakenly believe that belching will help relieve the symptoms of acid reflux, but they may be doing more harm than good.

About 10 percent of people who’ve had fundoplication surgery to correct GERD may develop a condition known as gas-bloat syndrome. The surgery prevents normal belching and your ability to vomit. Gas-bloat syndrome usually resolves on its own within two to four weeks following surgery. However, sometimes it can persist. In more serious cases, you may need to change your diet or receive counseling to help break your belching habit. In the most serious cases, additional surgery may be required to correct the problem.