What causes gastroesophageal reflux disease (GERD)?

Gastric acid from the stomach can sometimes flow past the sphincter and up the esophagus. In this video, Sharmila Anandasabapathy, MD, a gastroenterologist at The Mount Sinai Medical Center, discusses the most common causes of GERD.

GERD is caused by the valve between the stomach and esophagus not staying closed tightly enough to prevent stomach contents from going back into the esophagus.
Dr. Kevin A. Ghassemi, MD

GERD occurs for a variety of reasons. One of the most common causes is a weakened muscle (sphincter) that allows stomach acid or food to move back into the esophagus. Unfortunately, we’re not sure why this happens in some people. It’s important to know that nobody is immune to GERD. Overweight and older people might be more likely to have it, but physically fit, younger people can get it, too.

This content originally appeared online at UCLA Health.

GERD is caused by a malfunction of the bottom muscle of the swallowing tube, causing it to open irregularly about 100 times a day.

Gastroesophageal reflux disease (GERD) occurs when there is an imbalance between the normal defense mechanisms of the esophagus and offensive factors such as acid and other digestive juices and enzymes in the stomach. Often, the barrier between the stomach and the esophagus is impaired by weakening of the muscle (lower esophageal sphincter) or the presence of a hiatal hernia, where part of the stomach is displaced into the chest. Hiatal hernias, however, are common, and not all people with a hiatal hernia have reflux. A major cause of reflux is obesity, whereby increased pressure in the abdomen overcomes the barrier between the stomach and the esophagus. Obesity, pregnancy, smoking, excess alcohol use and consumption of a variety of foods such as coffee, citrus drinks, tomato-based products, chocolate, peppermint and fatty foods may also contribute to reflux symptoms.

Risk factors for gastroesophageal reflux disease (GERD) include:

  • Being overweight or obese
  • Smoking
  • Pregnancy
  • Having a hiatal hernia where the stomach moves up above the diaphragm
  • Diabetes
  • Excess alcohol intake
  • Asthma

Nicotine products—cigars, cigarettes or gum to help stop smoking—cause the valve at the top of the stomach to relax, allowing stomach acid to flow back into the esophagus. Smoking also can irritate an esophagus already tender from the backflow of stomach acid.

Gastroesophageal reflux disease (GERD) is caused by a breakdown in the barrier between the stomach and the esophagus, which allows acid and other digestive fluids in the stomach to come up into the esophagus. Though the stomach lining is resistant to the harsh nature of these fluids, the esophagus is not. When acid enters the esophagus, you may experience a wide variety of symptoms.

Gastroesophageal reflux disease occurs when there is a defective reflux barrier. The stomach contents including acid back up into the esophagus and damage the lining of the esophagus. Normally the lower esophageal sphincter (LES) pressure acts as a valve that prevents reflux of contents, specifically acid, from the stomach. The LES pressure is lowered in pregnancy as well as in certain diseases (scleroderma). Reflux symptoms also occur when patients have a hiatal hernia (part of the stomach resides in the thoracic cavity) or in obese patients in whom there is increased intra abdominal pressure which overcomes the LES allowing for reflux of stomach acid. Lower LES pressure can be due to eating certain foods-chocolate, peppermint, alcohol- and can occur as a side effect of certain medications such as theophylline, nitrates, sedatives, anticholinergics, calcium channel blockers, alpha adrenergic antagonists, prostaglandins.

Dr. Lawrence S. Friedman, MD

Malfunction of the lower esophageal sphincter (LES) is the main factor contributing to gastroesophageal reflux disease (GERD). Other factors have also been identified. In one study, about half of reflux patients exhibited impaired motility of the stomach—the inability of the stomach muscles to contract in a normal fashion. This might lead to delayed emptying of the stomach, increasing the risk that acid will reflux back into the esophagus. A failure of peristaltic (wavelike movement of intestinal muscles) contractions to clear the esophagus of acid that has refluxed, a lessening of the esophageal lining's ability to resist damage or a shortage of saliva (which has a neutralizing effect on acid) can play a part as well.

Episodes of reflux often go unnoticed, but when reflux is excessive and frequent, the gastric juices irritate the gullet, producing pain, which is experienced as heartburn. Sometimes acid regurgitates all the way up to the mouth and may come up forcefully as vomit or as a "wet burp." Most symptoms of GERD are transient and occur only in certain situations, such as after a big meal, a time of stress or when a person bends over or lies down.

Other medical conditions can also contribute to GERD. As many as 70 percent of asthma patients, for example, have reflux. It's not clear, however, whether asthma is a cause or an effect. Still, asthma often improves when GERD is treated. Other illnesses that sometimes contribute to reflux include diabetes, peptic ulcers and some types of cancer.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Fat doesn't just pose problems for your belly and subway turnstiles; it also can mess with your throat. About half of obese people have the chest-burning condition called GERD (gastro-esophageal reflux disease).

The thinking is that extra fat in the belly pushes down on your stomach, thereby opening the angle of the GE junction and pushing it toward the chest (it's at an acute angle to keep food from going back up your throat every time you eat). The more open angle makes it easier for acid and food to be pushed back up. Plus, the extra fat in the belly puts pressure on the contents of our bowel. More pressure, more GERD.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.