1. Hannah, Janet RN, CGRN

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Smoking and Its Noncancer Effects on the Digestive System

Smoking harms nearly every organ of the body, causing many diseases, and generally reduces the overall health of the smoker. The inhalation of cigarette smoke is responsible for alterations throughout the body, including the digestive system. Tobacco smoke contains a deadly mix of more than 7,000 chemicals; hundreds are toxic, and about 70 can cause cancer. (Office on Smoking and Health, National Center for Chronic Disease Prevention and Health Promotion, 2013).


Smoking is known to be associated with various gastrointestinal tract cancers such as oral, mouth, throat, esophageal, and colon (U.S. Department of Health and Human Services, 2007). In addition to the cancer link, smoking has several noncancer effects on the body and the gastrointestinal tract. This aspect can have serious consequences on health because the function of the digestive system is to convert foods into the nutrients the body needs to survive. Smoking alters the gastrointestinal tract's ability to function correctly.


Clinical research has shown repeatedly that smoking can be a direct cause of the following: bad breath, discoloration of the teeth, gingivitis, and dental cavities (Katz, 2013). Cigarette smoke causes increased salivation, which can result in tooth enamel erosion. Smoking directly obstructs the ability for cells in the mouth tissues to function naturally (Katz, 2013). It also interferes with healthy blood flow to the mouth, tongue, gums, and teeth roots. This causes an increase in plaque build-up and risk of leukoplakia and contributes to bone loss in the jaw (Katz, 2013).


Cigarette smoke is absorbed in saliva and then swallowed (Cope, 2011). There are changes in the gastric mucosa caused by this swallowed smoke (Cope, 2011). There is an increased risk of developing other common disorders, including heartburn and peptic ulcers (Bennett, 1972). Heartburn appears to increase in incidence with smoking due to the decrease of strength of the lower esophageal sphincter, which allows stomach acids to reflux. The Surgeon General stated in a report published as early as 1989 that ulcers, especially duodenal ulcers, are more likely to occur and less likely to heal or respond to treatment and has a higher morbidity rate if someone smokes (Raymond, 2006).


Edwards and Coghill, in their study of pathologically documented atrophic gastritis, found that in people older than 50 years, gastritis was more commonplace in heavy cigarette smokers. (Bynum, Soloman, Johnson, & Jacobson. 1972). There appears to be an association with smoking and an increase in the Helicobacter pylori bacteria, which cause the formation of the ulcers (Staff Writers, 2003). Usually stomach acid is neutralized by our foods we eat, but smoking reduces the amount of sodium bicarbonate produced by the pancreas. This, along with studies that indicate smoking actually increases the amount of acid produced by the stomach, causes increased formation of peptic ulcers. This effect seems to be short-lived and returns to normal within 30 minutes after a person quits smoking (Smoking and Your Digestive System, 2006). Smoking may increase the risk of developing gallstones. Several studies show that the risk may be increased for women, but these results are not conclusive.


Research indicates that current smokers have an increased risk of development of Crohn disease in comparison with nonsmokers. Smoking worsens Crohn disease if you already have it (Cosnes, 2008). Smokers who have Crohn disease have more severe ileal disease. It is linked to a higher rate of relapse, higher rates of surgery, and increased need for immune-suppressive therapy. The risk for women is higher than that for men. Former smokers who no longer smoke still remain at risk for Crohn disease. The theory is that smoking might lower the intestine's defenses, decrease blood flow to the intestines, or cause changes in the immune system that increases inflammation (Staff Writers, 2003). On the contrary, smoking tends to lessen the severity of ulcerative colitis activity and helps stabilize the disease.


The liver is responsible for handling the management of medications, alcohol, and other toxins that are in the body and to eliminate them from the body. There is evidence that smoking interferes with the liver's capacity to handle these substances. Medication doses may have to be altered to obtain effective treatments for some illness. Some research also proposes that smoking may exacerbate liver disease caused by excessive alcohol intake. There is an indication that the effects of smoking on the liver's ability to process medications return to normal once the person stops smoking (Smoking and Your Digestive System, 2006).


Smoking increases the number of colon polyps, 2-3 times the risk for adenomas. There is a 30% increased risk of colon cancer in smokers (Medscape) (Raymond, 2006).


To conclude, smoking is not good for the health of an individual on any level. Those who smoke need to be educated on the harmful effects to the body and encouraged to stop smoking.


Janet Hannah, RN, CGRN


Inova Loudoun Ambulatory Surgery Center


Leesburg, Virginia




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