---

Background: The detrimental effects of partially hydrogenated vegetable oils (PHVOs) on apolipoproteins have been reported from several parts of the world; however, few data are available in this regard from the understudied region of the Middle East. The present study aimed to evaluate the association between type of vegetable oils, serum lipids and apolipoprotein levels among Iranians.Methods: In this cross-sectional study, data of 1772 people (795 men and 977 women) aged 19 to 81 years were used. Participants were selected through multistage cluster random sampling method from three counties of Isfahan, Najafabad and Arak, Iran in Isfahan Healthy Heart Program (IHHP). To assess participants' usual dietary intakes, a validated food frequency questionnaire was used. Consumption of hydrogenated vegetable oil (commonly consumed for cooking in Iran) and margarine was considered as the category of PHVOs. Consumption of soy, sunflower, corn, olive and canola oils was considered as non-HVOs category. After an overnight fasting, serum colestrol (total, LDL, and HDL) and triglyceride as well as apolipoproteins A and B were measured using standard methods.Findings: Participants with the highest intake of non-HVOs and PHVOs were younger and had lower weight than those with the lowest intake. High consumption of non-HVOs and PHVOs was associated with lower intake of energy, carbohydrate, dietary fiber, and higher intake of fruits, vegetables, meat, milk and grains. No overall significant differences were found in serum lipids and apolipoprotein levels across quartiles of non-HVOs as well as PHVOs after controlling for potential confounding.Conclusion: There was no significant association between hydrogenated or non-hydrogenated vegetable oil and serum lipid and apolipoprotein levels. Further studies are needed to explore this association.