OBJECTIVE The aim of this study was to determine risk factors for the development of sessile serrated adenomas (SSA/Ps) as well as to study differences between groups with SSA/Ps and conventional adenomas (tubular, tubulovillus and villus) in the general population. METHODS One hundred patients with normal colonoscopies, 27 patients with 53 SSA/Ps and 69 patients with 156 conventional adenomas were studied, epidemiological data were collected and calculations of body mass index and waist-to-hip ratio were performed prior to endoscopy. A univariate and a multivariate logistic regression analysis were performed using Stata 9.0. RESULTS SSA/Ps had a positive association with increasing age (p = 0.01), heavy smoking (≥20 packet years) (p = 0.001) and past history of polyps (p = 0.004) in comparison to normal population. SSA/Ps showed an inverse association with conventional adenomas for diabetes mellitus (p < 0.001) and arterial hypertension (p = 0.001). Meanwhile, female sex was positively associated with SSA/P development in comparison to conventional adenomas (p = 0.031). CONCLUSIONS Heavy smoking as a significant risk factor for developing SSA/Ps was confirmed from this study. It also seemed that patients with diabetes mellitus and/or hypertension developed conventional adenomas more frequently than SSA/Ps; on the contrary, females were at higher risk of developing SSA/Ps than conventional adenomas.