Mojgan Amiri - Nutrition and Food Security research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Hamidreza Raeisi-Dehkordi - Nutrition and Food Security research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Amin Salehi-Abargouei - Nutrition and Food Security research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran

Background and Aim: Although a number of clinical trials have examined the effect of canola oil (CO) on body weight and composition, they were inconsistent in their results. so we examined the effect of CO on body weight and composition using systematic review and meta-analysis of controlled clinical trials.Methods: PubMed, Scopus and Google scholar were searched up to February 2018. Cochrane collaboration tool was used to assess the risk of bias, Random effects model was used for calculating the overall effects on body weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist to hip ratio (WHR), android to gynoid ratio (A/G), lean and body fat mass.Results: Twenty-five studies were included in the systematic review. The meta-analysis revealed that CO consumption reduces body weight [Weighted Mean difference (WMD)= -0.30 kg, 95% confidence interval (CI): -0.52, -0.08, p= 0.007; n=23] particularly in participants with type 2 diabetes (WMD= -0.63 kg, 95% CI: -1.09, -0.17, p= 0.007), in studies with parallel design (WMD= -0.49 kg, 95% CI: -0.85, -0.14, p= 0.006), in non-feeding trials (WMD= -0.32 kg, 95% CI: -0.55, -0.09, p= 0.006) and when CO is compared to saturated fat (WMD= -0.40 kg, 95% CI: -0.74, -0.06, p= 0.019). CO did not significantly affect other markers of body fat and composition (P> 0.05). Conclusion: The present study revealed that canola oil consumption favorably decreases body weight but no other anthropometry indices. Further well designed clinical trials which target the body weight and composition as the primary outcome are needed.

Canola oil; Rapeseed oil; Body weight; Obesity; Body mass index; Systematic review; Meta-analysis