The relation between dietary intake of vegetable oils and serum lipids and apolipoprotein levels in central Iran

BACKGROUND The detrimental effects of partially hydrogenated vegetable oils (PHVOs) on apolipoproteins have been reported from several parts of the world. However, little data is available in this regard from the understudied region of the Middle East. The present study therefore tried to evaluate the association between type of vegetable oils and serum lipids and apolipoprotein levels among Iranians. METHODS In this cross-sectional study, data from 1772 people (795 men and 977 women) aged 19-81 years, who were selected with multistage cluster random sampling method from three cities of Isfahan, Najafabad and Arak in "Isfahan Healthy Heart Program" (IHHP) (Iran), was used. To assess participants' usual dietary intakes, a validated food frequency questionnaire was used. Hydrogenated vegetable oil (commonly consumed for cooking in Iran) and margarine were considered as the category of PHVOs. Soy, sunflower, corn, olive and canola oils were considered as non-HVOs. After an overnight fasting, serum cholesterol (total, low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol) and triglyceride as well as apolipoproteins A and B were measured using standard methods. RESULTS Participants with the highest intakes of non-HVOs and PHVOs were younger and had lower weight than those with lowest intakes. High consumption of non-HVOs and PHVOs was associated with lower intakes of energy, carbohydrate, dietary fiber, and higher intakes of fruits, vegetables, meat, milk and grains. No overall significant differences were found in serum lipids and apolipoprotein levels across the quartiles of non-HVOs and PHVOs after controlling for potential confounding. CONCLUSION We did not find any significant associations between hydrogenated or nonhydrogenated vegetable oil and serum lipid and apolipoprotein levels. Thus, further studies are needed in this region to explore this association.