Acid reflux is one of the top health-related internet search queries, a very common symptom of burning pain felt internally around the lower chest area, caused by stomach acid flowing back up into the food pipe.
Gastroesophageal reflux disease (GERD, or GORD for gastro-oesophageal reflux disease) is acid reflux more than twice a week.
Use this page to learn what causes acid reflux and gastroesophageal reflux disease. Also get an overview of symptoms, and how the condition is diagnosed. We outline the treatment options available for the management of the condition, and how lifestyle measures may have preventive benefit.
Contents of this article:
You will also see introductions at the end of some sections to any recent developments that have been covered by MNT's news stories. Also, look out for links to information about related conditions.
Fast facts on acid reflux
Here are some key points about acid reflux. More detail and supporting information is in the main article.
- Acid reflux is also known as heartburn, acid indigestion, or pyrosis.
- It happens when some of the acidic stomach contents go back up into the esophagus.
- Acid reflux creates a burning pain in the lower chest area, often after eating.
- Gastroesophageal reflux disease (GERD) is acid reflux that persists more often than twice a week.
- GERD is very common in the US and other western populations.
- Lifestyle risk factors include obesity and smoking.
- Drug treatments are the mainstay of therapy and are available on prescription and over the counter.
- Left untreated, gastroesophageal reflux disease can have serious complications, including an increased risk of cancer.
What is acid reflux?
Acid reflux is when some of the acid content of the stomach flows up into the esophagus - into the gullet, which moves food down from the mouth.
The stomach contains a strong acid, hydrochloric acid, to help with the efficient digestion of food and to protect against undesirable microbes such as bacteria.1
The lining of the stomach is specially adapted to produce this acid, and also to protect the digestive organ against its own corrosive secretion, but the higher gut is not protected from this acid.
A ring of muscle - the gastroesophageal sphincter - normally protects the esophagus from the contents of the stomach by acting as a valve that lets food into the stomach but not back up into the esophagus.2 When this valve fails and stomach contents are regurgitated into the esophagus, the symptoms of acid reflex are felt, such as heartburn. This is also known as pyrosis or acid indigestion.
Exact figures vary but acid reflux is considered very common, and diseases resulting from acid reflux are the most common gut complaint seen by US hospital departments.3
The American College of Gastroenterology says that over 60 million Americans experience heartburn at least once a month, and at least 15 million as often as daily.4
Gastroesophageal reflux disease has the highest burden in western countries, affecting an estimated 20-30% of the population.5 Americans are especially prone to GERD,6 likely due to a higher prevalence of several lifestyle risk factors, which are explored below.
Recent developments on reflux disease statistics
Acid reflux 50% more common than ten years ago. This study, published in the journal Gut in December 2011, yielded detailed sets of statistics about changes in the prevalence of acid reflux symptoms and disease in the Norwegian population.
What causes acid reflux?
We all may experience acid reflux occasionally, often associated with certain food and drink. Recurrent acid reflux that leads to disease has other causes and risk factors, and is termed gastroesophageal reflux disease (GERD or GORD).
Gastroesophageal reflux disease is seen in people of all ages, sometimes for unknown reasons (idiopathic).7 Often the cause is attributable to a lifestyle factor, but it can also be due to causes that cannot always be prevented.
One such cause of GERD is a hiatal (or hiatus) hernia. This is an anatomical abnormality where a hole in the diaphragm allows the upper part of the stomach to enter the chest cavity, sometimes leading to GERD.
Pregnancy is also sometimes a cause of acid reflux due to extra pressure being placed on the internal organs.
Other risk factors are more easily controlled and often directly linked to modifiable lifestyle or dietary issues, including:7-9
- Smoking (active or passive)
- High intake of table salt
- Low dietary fibre intake
- Low levels of hysical exercise
- Medications, including drugs for asthma, calcium-channel blockers, antihistamines, painkillers, sedatives, and antidepressants.
Individuals may report an association with certain food and drinks but research suggests there is not any link between gastroesophageal reflux disease and intake of alcohol, coffee or tea.8
The animation from YouTube below, produced by the Mayo Clinic, shows how stomach acid looks in the digestive system, and the action of the gastroesophageal sphincter (valve) as it allows reflux into the esophagus.
Signs and symptoms of acid reflux
Acid reflux, whether it is a harmless, isolated episode of the sort we all experience at some point, or the persistent problem of gastroesophageal reflux disease, usually produces the same main symptom:2,4,7
Heartburn is a discomfort - happening in the esophagus and felt behind the breastbone area - that takes the form of a burning sensation and which tends to worsen when the person lies down or bends over.2 It can last for several hours and also tends to worsen after eating food.4
The burning pain may move up toward the neck and throat as stomach fluid can reach the back of the throat in some cases, producing a bitter or sour taste.4
We all experience heartburn occasionally, due to simple acid reflux, but if this occurs regularly - two or more times a week - it is termed gastroesophageal reflux disease, or GERD for short.4,7 GERD can also be signalled by other symptoms, including:4,7
- Dry, persistent cough
- Asthma and recurrent pneumonia
- Throat problems - soreness, hoarseness, or laryngitis (voice box inflammation)
- Difficulty or pain when swallowing
- Chest or upper abdominal pain
- Dental erosion
- Bad breath.
On the next page we look at tests and diagnosis for acid reflux, prevention, available treatments, over-the-counter remedies and prevention of acid reflux through lifestyle control.