Heartburn is more common among the overweight and obese, people who smoke and pregnant women, although most people experience heartburn at some point in their lives.
There are no racial predispositions for the development of gastro-oesophageal reflux disease (GORD), the condition most often associated with heartburn, but middle-aged Caucasian men seem to be at increased risk for Barrett’s oesophagus, one of the more serious complications of GORD (see "Possible complications").
Heartburn affects people of all ages, including babies and young children. In babies, milk tends to flow back up into the oesophagus and out of the mouth, simply because the lower oesophageal sphincter isn’t fully developed yet.
In some infants, this could lead to gastro-oesophageal reflux disease (GORD) and more severe symptoms. Fortunately, most children outgrow the condition by two years of age – a result of the anti-reflux mechanisms becoming stronger.
Over the years, researchers have identified a number of possible factors that could increase a person’s risk for heartburn. These include:
Weight and obesity
A high body mass index (a BMI of more than 25) and an unhealthy waist circumference (more than 102cm in men and 88cm in women) can affect:
• The pressure inside the stomach and therefore the pressure on the lower oesophageal sphincter
• The amount of bile and pancreatic enzymes produced by the body
• The risk for hiatus hernia
• The gradient of the lower oesophageal sphincter, which helps to keep the stomach contents out of the oesophagus
These factors may all contribute to heartburn and gastro-oesophageal reflux disease (GORD), the condition most often associated with heartburn.
In one study, 37% of overweight and obese participants had GORD. Worryingly, there’s also a well-documented association between an elevated BMI and oesophageal cancer.
Weight loss can make a significant difference if you’re overweight or obese, and suffer from heartburn.
The more you smoke, or the more you’re exposed to second-hand smoke, the greater your risk for heartburn and GORD. Research shows that tobacco smoke:
• Increases stomach acid production
• Reduces the rate at which the stomach empties
• Decreases the pressure on the lower oesophageal sphincter, which allows stomach acid to flow back up into the oesophagus
• Promotes the movement of bile salts from the intestine into the stomach, which makes stomach acid more harmful
• Injures the oesophagus, making it less able to resist damage from stomach acid
The good news is that once you quit smoking, the body’s anti-reflux mechanisms once again start to work as they should.
Drinking alcohol, especially in large quantities, may increase acid secretion in the stomach, which could increase the volume of reflux into the oesophagus.
The alcohol itself may also damage the delicate lining of the oesophagus. In this way, drinking alcohol may increase the risk for heartburn and, potentially, GORD.
Drinking less alcohol, or no alcohol at all, could be an effective way of controlling heartburn.
If you suffer from heartburn, chances are that one or more of your family members get heartburn, too – your mother, father, brother or sister. Research shows that genetics could up your risk for heartburn and GORD.
A 2002 study of Swedish twins showed that genetically alike identical (monozygotic) twins were twice as likely to share symptoms of GORD as less genetically alike fraternal (dizygotic) twins.
Inherited genes, and not just environmental factors (e.g. similar lifestyle patterns), could therefore play a role in the development of GORD.
Research shows that both women and men experience a similar percentage of heartburn, but that women may experience symptoms more often than men. Women also tend to report more severe symptoms.
The fact that overweight and obesity are more prevalent among women also plays a role. The much-cited American Nurses Health Study, for example, showed that women with a BMI greater than 22.5 experienced more frequent GORD symptoms. This increased to an odds ratio of almost three for those with a BMI greater than 35.
Another factor that increases a woman’s risk for heartburn is pregnancy.
The hormonal changes during pregnancy can lead to the relaxation of the lower oesophageal sphincter, which then leads to more frequent reflux and/or greater volumes of reflux.
Another factor is the increased size of the uterus during pregnancy. As the uterus presses on the stomach, it creates pressure inside of it, which increases the tendency to reflux.
Certain medicines and supplements can cause heartburn. The active ingredients in some relax the lower oesophageal sphincter, causing reflux, while others irritate the oesophagus.
The list of medications that may cause heartburn includes:
• Medication used in the treatment of osteoporosis
• Iron supplements
• Quinidine, used to treat heart-rhythm disorders
• Non-steroidal anti-inflammatories, i.e. painkillers like ibuprofen
• Potassium supplements
• Tricyclic antidepressants, e.g. Tryptanol and Trepiline
• Calcium channel blockers, used to treat high blood pressure, migraines and angina
• Medication that contains codeine, e.g. Myprodol and Adco-Dol
• Sedatives for anxiety or sleeplessness
If your medication is causing heartburn, or making GORD symptoms worse, talk to your doctor about possible alternatives.
How common is it?
Heartburn is believed to affect 25% of adults in the western world at least once a month, while 5% experience heartburn daily. If extrapolated statistics are to be believed, at least 2.5 million South Africans regularly experience heartburn.
According to local gastroenterologist Dr Estelle Wilken, who is based at Tygerberg Hospital in Bellville, heartburn certainly is one of the most common medical problems in South Africa, and a symptom that’s directly linked to the growing incidence of overweight and obesity in this country.
South Africa has the highest rate of overweight and obesity in sub-Saharan Africa, with up to 70% of women and 33% of men being classified as overweight or obese.
Worldwide, the prevalence of gastroesophageal reflux disease (GORD), one of the common causes of heartburn, appears to be highest in North America and Europe.
Unfortunately, insufficient data from Africa means that the extent of the problem is less clear here. No population-based studies have been done in Africa.
- Reviewed by Dr Estelle Wilken, senior specialist in Internal Medicine and Gastroenterology at Tygerberg Hospital, March 2017