Smoking is a dangerous habit and can result in many health risks for the smoker and the people around them. The properties of cigarette smoke can reduce the ability of the Lower Oesophageal Sphincter (LES) to contract or close allowing acid to reflux.
Cigarette smoke, particularly nicotine, can dry out your mouth which decreases saliva production. Saliva is swallowed all the time to aid digestion and it also lubricates the oesophagus and neutralises stomach acid.