The following table summarizes the common fatty acids found in foods and indicates the current knowledge about their effect on the human body.
Fatty acids and known biological effect
Fatty acid Biological effect on body Found in
SATURATED
Lauric acid C12:0 Increases LDLs and HDLs and promotes thrombosis coconut oil and other tropical fats
Myristic acid C14:0 Increases LDLs and HDLs and promotes thrombosis coconut oil and other tropical fats
Palmitic acid C16:0 Increases LDLs and HDLs and promotes thrombosis Palm oil and other tropical fats widely used in the food industry as a cheap replacement for trans fats
Stearic acid C18:0 Does NOT increase LDLs and HDLs Most vegetable fats and oils including soybean oil, canola oil and sunflower oil, cocoa butter, and fully hydrogenated oils.
MONO-UNSATURATED
cis isomers
Palmitoleic acid C16:1 Reduces LDL if replacing saturated fat and reduces total cholesterol with dietary carbohydrate Avacado oil,nuts,seeds,beef tallow,some fish oils
Oleic acid C18:1 Reduces LDL if replacing saturated fat and reduces total cholesterol with dietary carbohydrate Canola oil, high oleic sunflower oil,avacado oil,nuts,seeds,beef tallow,some fish oils
trans isomers
Elaidic acid C18:1 Increases LDLs similar to palmitic and myristic saturated fatty acids AND decreases HDLs. Raises the total cholesterol-to-HDL ratio. Induces systemic inflammation and endothelial dysfunction. Partially hydrogenated vegetable oils found in trans fat containing margarines and shortenings.
POLY-UNSATURATED
n-3 Fatty acids
alpha-Linolenic acid C18:3 Lowers CVD risk Soybean oil,canola oil,flaxseed oil, walnuts
Eicosapentaenoic acid (EPA) C20:5 Important for nervous system development and maintenance Algae, fish oil
Docosapentaenoic acid C22:5 Important for nervous system development and maintenance Algae, fish oil
Docosahexaenoic acid(DHA) C22:6 Important for nervous system development and maintenance Algae, fish oil
n-6 Fatty acids
Linoleic acid C18:2 Lowers LDL and total cholesterol Liquid vegetable oils not including hard tropical fats
Arachidonic acid C20:4 Precursor for eicosanoids
Conjugated Linoleic acid C18:2 Anti carcinogenic properties Butter, meat fat
This is an absolutely excellent table summarizing the individual effects of fatty acids on human metabolism.