Abstract
Background: Consuming tobacco is a major addiction worldwide. Smoking tobacco in the form of cigarette or beedi is prevalent in both males and females. Smoke of cigarette and beedi contains more than 2000 different toxic materials. These toxic materials produce local as well as systemic tissue damage. The damage caused by this smoke is mostly due to the oxidative stress produced by the free radicals due to smoking.

Aims and Objectives: The aim of the study is to find out the level of oxidative stress in smokers and compare it with the non-smoking subjects of the same age group. Furthermore, this study aims to find out relationship of pack-years of smoking with the oxidative stress in the smokers.

Materials and Methods: A total of 30 smokers having a history of more than 10 pack-years of smoking and 30 non-smoker subject of the age group of 40–70 years of age with no major illness were selected for the study. The serum superoxide dismutase (SOD) enzyme level was measured. The estimated SOD level was compared in both the groups.

Results: When both the groups were compared for the serum SOD level, it was found that the SOD level was significantly low in the smokers as compared to non-smokers. Furthermore, there was a significant negative correlation between the pack-years of the smoking and the serum SOD level.

Conclusion: The result of the study shows that smoking enhances oxidative stress by decreasing the level of lifesaving antioxidant enzymes in the body. This decrease in levels of antioxidant enzymes makes the smokers prone to various diseases such as coronary artery disease, chronic obstructive pulmonary disease, and cancers.

Key words: Smoking; Superoxide Dismutase; Oxidative Stress; Pack-years