Table 1

Major Classes of Fatty Acids

FamilyFatty AcidsFormulaSource
I omega-9Oleic acidC18:1Most vegetable oils (canola, olive); animal fats
II omega-6Linoleic acidC18:2Many vegetable oils (corn, safflower, soybean)
Arachidonic acidC20:4Poultry, meats
III omega-3α-linolenic acidC18:3Selected vegetable oil (flaxseed, canola)
EPAC20:5Marine oils and fish
DHAC22:6Marine oils and fish
IV saturated fatsPalmitic acidC16:0Animal and vegetable fats
Stearic acidC18:0Butter, palm oil, kernel oil, coconut oil, and animal fats

DHA = docosahexaenoic acid; EPA = eicosapentaenoic acid.

  • The omega number refers to the position of the first double bond from the methyl end of the molecule.

  • The notation shows the total number of carbon atoms and total number of double bonds. Adapted with permission from Lavie et al. (2).