The health effects of saturated fat, particularly tropical oil, on cardiovascular disease are unclear. We investigated the effect of tropical oil (palm and coconut oils), lard, and other common vegetable oils (soybean and rice bran oils) that are widely used in tropical and Asian countries on lipid profiles. We performed an umbrella review of meta-analyses and systematic reviews. Electronic databases (Medline, Scopus, Embase, and Cochrane) were searched up to December 2018 without language restriction. We identified nine meta-analyses that investigated the effect of dietary oils on lipid levels. Replacement of polyunsaturated fatty-acid-rich oils (PUFAs) and monounsaturated FA-rich oils (MUFAs) with palm oil significantly increased low-density lipoprotein cholesterol (LDL-c), by 3.43 (0.44–6.41) mg/dL and 9.18 (6.90–11.45) mg/dL, respectively, and high-density lipoprotein cholesterol (HDL-c), by 1.89 (1.23–2.55) mg/dL and 0.94 (−0.07–1.97) mg/dL, respectively. Replacement of PUFAs with coconut oil significantly increased HDL-c and total cholesterol –by 2.27 (0.93–3.6) mg/dL and 5.88 (0.21–11.55) mg/dL, respectively—but not LDL-c. Substituting lard for MUFAs and PUFAs increased LDL-c–by 8.39 (2.83–13.95) mg/dL and 9.85 (6.06–13.65) mg/dL, respectively—but not HDL-c. Soybean oil substituted for other PUFAs had no effect on lipid levels, while rice bran oil substitution decreased LDL-c. Our findings show the deleterious effect of saturated fats from animal sources on lipid profiles. Replacement of unsaturated plant-derived fats with plant-derived saturated fats slightly increases LDL-c but also increases HDL-c, which in turn may exert a neutral effect on cardiovascular health.

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Objectives Cooking oils are composed of various fatty acids (FA) with different proportions which could influence on cardiovascular disease (CVD) differently. The effect of tropical oil consumption and the negative health impact of saturated fats consumption on CVD are controversial. Methods We performed an umbrella review of the systematic reviews and meta-analyses that investigated the effect of edible oils by isocaloric substitution for other oils consumed for at least 2 weeks on lipid profiles and CVD. Electronic databases including Medline, Scopus, Embase and Cochrane were searched until December 2018 by 2 independent reviewers without restriction of language and year of publication. Results The umbrella review identified 9 meta-analyses and 2 systematic reviews investigated the effect of oils on lipid levels and CVD, respectively. Corrected covered area was 7.4% illustrating the moderate overlap of primary trials. Our study demonstrated that replacement of polyunsaturated FA-rich oils (PUFAs) and monounsaturated FA-rich oils (MUFAs) by palm oil consumption significantly increased LDL-cholesterol by 4.75 mg/dL (95%CI: 0.45, 9.06) and 9.26 mg/dL(95% CI: 3.01, 15.51), respectively and HDL-cholesterol by 1.89 mg/dL (95%CI: 1.23, 2.55) and 0.53 mg/dL (95%CI: −1.71, 2.77), respectively. However, replacement of PUFAs or other saturated fats by coconut oil significantly increased HDL-c by 2.27 mg/dL (95%CI: 0.93, 3.6) and 1.48 mg/dL (95%CI: 0.20, 2.76), respectively but not LDL-c. The substitution of lard for MUFAs and PUFAs showed the increasing of LDL-c by 8.39 mg/dL (95%CI: 2.83, 13.95) and 9.85 mg/dL (95%CI: 6.06, 13.65), respectively but there was no significant effect on HDL-c. Soybean oil substituted for other PUFAs had no different effect on lipid levels while rice bran oil substitution decreased LDL-c. The association of edible oil consumption and the cardiovascular event and mortality could not be revealed due to small number of the studies. Conclusions Our study confirmed the deleterious effect of saturated fats on lipid profiles and showed the different effect of saturated fats from animal and plant. We demonstrated only the modest benefit of coconut oil on HDL-c but could not reveal the benefit on cardiovascular outcomes. Thus, dietary saturated fats should be replaced with either PUFAs or MUFAs. Funding Sources Thai Health Promotion Foundation.