How Does Smoking Cause Heartburn?

Seven Reasons to Kick the Habit for Your Digestive Tract

woman smoking cigarette which can cause heartburn
How does smoking cause heartburn and what else does it do to your digestive tract?. Tetra Images/Brand X Pictures/Getty Images

If you have heartburn and smoke, you've probably been told that smoking makes heartburn worse or can even cause it in the first place. How does this happen, and what else does smoking do to your digestive tract?

Heartburn and Smoking

There are numerous reasons for you to kick your smoking habit, but did you know that doing so may stop your heartburn? Smoking has negative effects beginning not only in your lungs, but throughout your digestive tract from your mouth to your stomach and beyond.

You may be surprised at just what effect smoking actually has on the body. If you can swallow it, you may wish to take a sneak peak at this list of diseases caused by smoking from head to toe.

6 Ways Smoking Causes Heartburn

Let's get back to your heartburn, and talk about the many ways in which smoking contributes to that awful burn in your throat and chest:

  1. Cigarette smoking slows the production of saliva. One of your body's defenses against damage to your esophagus is your saliva. There are even acid-neutralizing chemicals in saliva, called bicarbonates. Research shows that the saliva of smokers contains smaller amounts of bicarbonates, thus reducing the ability of the saliva to neutralize the acid. Saliva also bathes the esophagus and lessens the effects of acid that has refluxed up from the stomach, and helps wash the acid down to the stomach. The net effect of too little saliva (due directly to smoking) is more acid down and more acid up, both meeting in your esophagus to irritate and burn. (And, keep in mind that the worst part of this burn is not what you feel today, but what that damage can become in the future. Two of the biggest risk factors for esophageal cancer are smoking and heartburn.)
  1. Smoking stimulates the production of stomach acid. Too much stomach acid can both cause reflux of the acidic contents of your stomach into your esophagus, and more burning once it gets there due to greater acidity. In other words, too much stomach acid plays a double play on your esophagus.
  2. Smoking can weaken and relax the lower esophageal sphincter (LES), which is a valve at the junction between esophagus and stomach. If the LES isn't working properly or relaxes inappropriately, stomach contents can reflux back up into the esophagus. In addition to smoking, alcohol, as well as many drugs can lessen LES tone, compounding the problem,.
  1. Smoking changes stomach acid. Smoking also seems to promote the movement of bile salts from the intestine to the stomach, which makes the stomach acids more harmful.
  2. Smoking can directly injure the esophagus. Several chemicals in cigarette smoke can directly damage the lining of the esophagus. Once the esophagus is damaged, it is even more susceptible to further damage from acid reflux.
  3. Smoking slows digestion. Studies have shown that smokers have decreased gastric motility (digestion) while smoking, which can cause less efficient digestion because the stomach takes longer to empty. The longer food (and acid) is present in the stomach, the greater opportunity it has to be refluxed up into the esophagus.

Smoking's Effects On Other Areas of the Digestive System

The effects of smoking on the esophagus should be enough, but let's descend further through the digestive tract to see some of the ways.

Smoking and Peptic Ulcers

peptic ulcer is an open sore in the lining of the stomach or duodenum, the first part of the small intestine. The exact cause of ulcers is not known. A relationship between smoking cigarettes and ulcers, especially duodenal ulcers, does exist. The 1989 Surgeon General's report stated that ulcers are more likely to occur, less likely to heal, and more likely to cause death in smokers than in nonsmokers.

Why is this so? Doctors are not really sure, but smoking does seem to be one of several factors that work together to promote the formation of ulcers. For example, some research suggests that smoking might increase a person's risk of infection with the bacterium Helicobacter pylori (H. pylori). Most peptic ulcers are caused by this bacterium.

Stomach acid is also important in producing ulcers. Normally, most of this acid is buffered by the food we eat. Most of the unbuffered acid that enters the duodenum is quickly neutralized by sodium bicarbonate, a naturally occurring alkali produced by the pancreas.

Some studies show that smoking reduces the bicarbonate produced by the pancreas, interfering with the neutralization of acid in the duodenum. Other studies suggest that chronic cigarette smoking may increase the amount of acid secreted by the stomach.

Whatever causes the link between smoking and ulcers, two points have been repeatedly demonstrated: People who smoke are more likely to develop an ulcer, especially a duodenal ulcer, and ulcers in smokers are less likely to heal quickly in response to otherwise effective treatment. 

Smoking and Inflammatory Bowel Disease

Progressing even further in the digestive tract doesn't reduce the effects of smoking. There is a link between smoking and inflammatory bowel diseases such as Crohn's disease and ulcerative colitis.

Smoking and Colorectal Cancer

Finally, at the far end of the digestive tract smoking is still a problem. Colon cancer and rectal cancers are two of the well known cancers caused by smoking. In fact, it's currently thought that 12 percent of colon and rectal cancers are caused by smoking.

Bottom Line on Smoking, Heartburn, and Your Digestive Tract

We could go on some more about the damage caused by smoking, but hopefully taking a look at six ways in which smoking causes heartburn, and how damage is not limited to your digestive tract is enough. Better to take your time learning all you can about how to quit for good. Check out these reasons to kick the habit today.


Ness-Jensen, E., Hveem, K., El-Seraq, H., and J. Lagergren. Lifestyle Intervention in Gastroesophageal Reflux Disease. Clinical Gastroenterology and Hepatology. 2016. 14(2):175-82.e1-3.

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