Objective:To determine the association of smoking, alcohol and nonsteroidal anti-inflammatory drugs (NSAIDs) use with presence and virulence of Helicobacter pylori (H. pylori) infection in a representative sample of a random adult population of asymptomatic subjects. Methods:Non virulent 16S rRNA and virulent cag A and T genes from salivary samples of 854 asymptomatic subjects were determined using polymerase chain reaction. The presence and absence of virulent and non virulent infection was statistically compared with consumption of smoking, alcohol and NSAIDs. Results:The prevalence of infection in male and female subjects was found to be 69.25%and 66.90%, respectively. The prevalence of infection in the population of asymptomatic subjects with respect to consumption of alcohol was as follows:current (31.22%), former (52.20%) and never (43.58%). The prevalence of infection in the population of asymptomatic subjects with respect to smoking of cigarettes was as follows:current (88.80%), former (57.14%) and never (33.33%). The prevalence of infection in the subject population consuming NSAIDs and not consuming NSAIDs frequently was found to be 82.75%and 21.16%, respectively. Virulence in male and female subjects was found to be 60.00%and 50.00%, respectively. The presence of virulent infection in the population of asymptomatic subjects with respect to consumption of alcohol was as follows:current (28.57%), former (40.15%) and never (50.00%). The prevalence of virulent infection in the population of asymptomatic subjects with respect to smoking of cigarettes was as follows:current (79.32%), former (75.00%) and never (50.00%). The prevalence of virulent infection in the subject population consuming NSAIDs and not consuming NSAIDs frequently was found to be 88.23%and 66.66%, respectively. Conclusions:It can be concluded that smoking and NSAIDs consumption are aggravating factors for virulence of H. pylori and alcohol can inhibit H. pylori infection in asymptomatic subjects.