Comparison of canola oil and olive oil consumption on the serum lipid profile in adults: a systematic review and meta-analysis of randomized controlled trials

Abstract

Background and Aims

Several randomized clinical trials have investigated the effects of canola oil (CO) compared to olive oil (OO) on the serum lipid profiles in adults. However, the results of these studies are inconsistent. Thus, this study aimed to assess the comparison of CO and OO consumption on the serum lipid components in adults.

Methods and Results

The following online databases were searched until February 4^th, 2022: PubMed/Medline, Scopus, Clarivate Analytics Web of Science, Cochrane Central Register of Controlled Trials, and Google Scholar. The effect sizes were stated as the weighted mean difference (WMD) with 95% confidence intervals (CI). A total of 13 eligible trials were included in this meta-analysis. The results showed that the CO consumption, significantly reduced serum LDL-c (WMD: −6.13 mg/dl, 95%CI: −9.79, −2.46, p = 0.001), TC (WMD: −8.92 mg/dl, 95% CI: −13.52, −4.33, P < 0.001) and LDL-c/HDL-c ratio (WMD: −0.30; 95% CI, −0.53, −0.06, p = 0.01) levels compared to OO. There were no significant changes in the other components of the blood lipids.

Conclusion

The results of this review suggest that CO consumptionhas beneficial effects on LDL-c, TC, and LDL-c/HDL-c ratio compared to OO. Therefore, its replacement with OO can have cardioprotective impacts.

HIGHLIGHTS

• Consumption of canola oil (CO) and olive oil (OO), two widely consumed vegetable oils that are low in saturated fatty acids and rich in monounsaturated fatty acids have been recommended.

• We compared the effects of these two oils on lowering blood lipid levels

• We found that CO was the more effective oil to reduce low-density lipoprotein cholesterol (LDL-c), total cholesterol (TC), and LDL-c/high-density lipoprotein cholesterol (HDL-c) ratio, with no significant effects on HDL-c, triglyceride (TG), TC/HDL-c ratio, and very-low-density lipoprotein cholesterol (VLDL-c) levels compared to OO.

Keywords:

• Canola oil
• rapseed oil
• oliveoil
• TC
• LDL-c
• HDL-c
• TG
• VLDL-c

Authors’ contributions

B.P. conceived the study and designed the search strategy; B.P. and E.SH.Z. conducted the study selection; B.P. and E.SH.Z conducted data extraction; E.SH.Z. evaluated the risk of bias of included studies; S.S. conducted the data analysis and interpretation of results; H.SH. and E.SH.Z and F.SH. wrote the first draft of the manuscript; B.P. edited and revised the manuscript. All authors read and approved the final version of the manuscript.

Disclosure statement

All the authors declare that they have no conflict of interest.

Additional information

Funding

This meta-analysis was supported by the Iran University of Medical Science, Tehran, Iran.