Dietary Fats and Oils: Dietary Fats and Oils: Relation to Blood CholesterolRelation to Blood Cholesterol
Frank M. Sacks, MDProfessor, Nutrition Department, Harvard School of Public Health;
Professor of Medicine, Harvard Medical SchoolSenior Physician, Brigham & Women’s Hospital
LDL-cholesterolLDL-cholesterol
• The “bad” cholesterol• Goes into the arterial wall• Causes atherosclerosis• Lowering blood LDL-cholesterol by diet or by most
drugs reverses atherosclerosis, prevents heart attacks• In trials of dietary polyunsaturated fats, the decrease
in LDL-cholesterol matches the decrease in heart disease.
Types of fatty acids
Saturated Monounsaturated (Oleic acid)
Linolenic acid Linoleic
acid
Methyl group
Acid group
Polyunsaturated (Essential fatty acids)
N-6N-3
Based on Mensink & Katan 2003. Figure from Micha & Mozaffarian, Lipids 2010
Effects of Dietary Fats on LDL-Cholesterol
=0.032*
=-0.009*
=-0.019*
Poly-unsaturated
Mono- unsaturated
Saturated
percentage of calories vs. carbohydrate
Change inLDL-C
(mmol/L)
Change inLDL-C
(mmol/L)
=0.052*
=0.048*
=0.039*
=-0.004
16:0 (palmitic)
14:0 (myristic)
12:0 (lauric)
18:0 (stearic)
Effects of Individual Saturated Fatty Acids on LDL cholesterol
percentage of calories vs. carbohydrate
LDL cholesterol
Figure from Micha & Mozaffarian, Lipids 2010. Based on Mensink & Katan 2003.
Palm oil and Lard Increase LDL-Cholesterol Compared to Olive Oil: 3 weeks each oil, 17% energy
Palm
Olive
Lard
Tholstrup T. AJCN 2011
18-carbon fatty acids
Stearic acid Oleic acid
Linolenic acid Linoleic
acid
Methyl group
Acid group
Oleic acid trans
Meta-analysis of 60 controlled trials on dietary fats and blood lipids: effect of replacing
carbohydrate with cis- or trans-fat
Mensink..Katan. Am J Clin Nutr 2003;77:1146
The OmniHeart Study Diets: The OmniHeart Study Diets: Lower Carbohydrate Modifications of Lower Carbohydrate Modifications of
DASH DietDASH Diet
Emphasize:Fruits, Vegetables; High-protein foods including beans, whole grains, nuts, low-fat dairy, fish and poultry; Unsaturated Cooking Oils
Reduced in:Carbohydrates, Saturated Fats, Red Meat, Sweets, and Sugar-containing Beverages.
Higher unsaturated fat, higher protein lowered BP and improved lipid risk factors more than the original high-carbohydrate DASH diet.
OmniHeart: LDL-cholesterol (mg/dL)OmniHeart: LDL-cholesterol (mg/dL)All diets low in saturated fat, All diets low in saturated fat, healthful DASH-type dietary healthful DASH-type dietary
patternspatternsMean Change from
Baseline in Each Diet
BaselineHigh
CARB (DASH)
High PROT
High UNSAT
FAT
All 129 -12 -14 -13
LDL-C > 130 157 -20 -24 -22
LDL-C < 130 105 -4 -6 -5
Appel L, Sacks F, et al. JAMA 2007
Dietary Fats, Oils to Lower LDL-cholesterol and Prevent Heart Disease
• Best Choice:– Polyunsaturated vegetable oils
• Peanut, Soybean, Corn, Rapeseed, sesame
• Next Best– Monounsaturated vegetable oils
• Olive* (more benefits when polyphenols high)• High-oleic sunflower, safflower
• Unhealthful Choices:– Trans unsaturated oils– Animal fats, high in saturated fatty acids– Palm oil