Palm oil and blood lipid-related markers of cardiovascular disease: a systematic review and meta-analysis of dietary intervention trials.
BACKGROUND
Palm oil (PO) may be an unhealthy fat because of its high saturated fatty acid content.


OBJECTIVE
The objective was to assess the effect of substituting PO for other primary dietary fats on blood lipid-related markers of coronary heart disease (CHD) and cardiovascular disease (CVD).


METHODS
We performed a systematic review and meta-analysis of dietary intervention trials. Studies were eligible if they included original data comparing PO-rich diets with other fat-rich diets and analyzed at least one of the following CHD/CVD biomarkers: total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, TC/HDL cholesterol, LDL cholesterol/HDL cholesterol, triacylglycerols, apolipoprotein A-I and B, very-low-density lipoprotein cholesterol, and lipoprotein(a).


RESULTS
Fifty-one studies were included. Intervention times ranged from 2 to 16 wk, and different fat substitutions ranged from 4% to 43%. Comparison of PO diets with diets rich in stearic acid, monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs) showed significantly higher TC, LDL cholesterol, apolipoprotein B, HDL cholesterol, and apolipoprotein A-I, whereas most of the same biomarkers were significantly lower when compared with diets rich in myristic/lauric acid. Comparison of PO-rich diets with diets rich in trans fatty acids showed significantly higher concentrations of HDL cholesterol and apolipoprotein A-I and significantly lower apolipoprotein B, triacylglycerols, and TC/HDL cholesterol. Stratified and meta-regression analyses showed that the higher concentrations of TC and LDL cholesterol, when PO was substituted for MUFAs and PUFAs, were not significant in young people and in subjects with diets with a lower percentage of energy from fat.


CONCLUSIONS
Both favorable and unfavorable changes in CHD/CVD risk markers occurred when PO was substituted for the primary dietary fats, whereas only favorable changes occurred when PO was substituted for trans fatty acids. Additional studies are needed to provide guidance for policymaking.
From the Departments of Environmental Health Sciences (EF) and Epidemiology (CB), IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri," Milan, Italy; the Department of Food Science, Università di Parma, Parma, Italy (FB); the Department of Clinical Sciences and Community Health, University of Milan, IRCCS Ospedale Maggiore Policlinico, Milan, Italy (CA); and the Department of Policy Analysis and Public Management & Centre for Research on Health and Social Care Management, Università Bocconi, Milan, Italy (GF).
Elena
E
Fattore
From the Departments of Environmental Health Sciences (EF) and Epidemiology (CB), IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri," Milan, Italy; the Department of Food Science, Università di Parma, Parma, Italy (FB); the Department of Clinical Sciences and Community Health, University of Milan, IRCCS Ospedale Maggiore Policlinico, Milan, Italy (CA); and the Department of Policy Analysis and Public Management & Centre for Research on Health and Social Care Management, Università Bocconi, Milan, Italy (GF).
Cristina
C
Bosetti
From the Departments of Environmental Health Sciences (EF) and Epidemiology (CB), IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri," Milan, Italy; the Department of Food Science, Università di Parma, Parma, Italy (FB); the Department of Clinical Sciences and Community Health, University of Milan, IRCCS Ospedale Maggiore Policlinico, Milan, Italy (CA); and the Department of Policy Analysis and Public Management & Centre for Research on Health and Social Care Management, Università Bocconi, Milan, Italy (GF).
Furio
F
Brighenti
From the Departments of Environmental Health Sciences (EF) and Epidemiology (CB), IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri," Milan, Italy; the Department of Food Science, Università di Parma, Parma, Italy (FB); the Department of Clinical Sciences and Community Health, University of Milan, IRCCS Ospedale Maggiore Policlinico, Milan, Italy (CA); and the Department of Policy Analysis and Public Management & Centre for Research on Health and Social Care Management, Università Bocconi, Milan, Italy (GF).
Carlo
C
Agostoni
From the Departments of Environmental Health Sciences (EF) and Epidemiology (CB), IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri," Milan, Italy; the Department of Food Science, Università di Parma, Parma, Italy (FB); the Department of Clinical Sciences and Community Health, University of Milan, IRCCS Ospedale Maggiore Policlinico, Milan, Italy (CA); and the Department of Policy Analysis and Public Management & Centre for Research on Health and Social Care Management, Università Bocconi, Milan, Italy (GF).
Giovanni
G
Fattore
D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000178:diet therapy / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D003327:Coronary Disease / Q000178:diet therapy / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D018592:Cross-Over Studies; D004042:Dietary Fats, Unsaturated / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D006949:Hyperlipidemias / Q000097:blood / Q000178:diet therapy* / Q000503:physiopathology; D008055:Lipids / Q000097:blood; D000073878:Palm Oil; D010938:Plant Oils / Q000009:adverse effects / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D044242:Trans Fatty Acids / Q000009:adverse effects
D015415:Biomarkers; D004042:Dietary Fats, Unsaturated; D008055:Lipids; D010938:Plant Oils; D044242:Trans Fatty Acids; D000073878:Palm Oil