Research shows that smoking may decrease the strength of your lower esophageal sphincter so that food refluxes into your esophagus . Either coughing or inhaling smoke can weaken the LES by suddenly increasing abdominal pressure. The nicotine in tobacco also reduces the amount of saliva you produce, which your esophagus uses to clear acid.
As a result, smokers may be more prone to damage from reflux . In addition, smoking seems to produce a more toxic reflux material because it moves bile from your intestine to your stomach.