The evening primrose flower (O. biennis) produces an oil containing a high content ofγ-linolenic acid, a type of omega−6 fatty acid.
Omega−6 fatty acids (also referred to asω−6 fatty acids orn−6 fatty acids) are a family ofpolyunsaturated fatty acids (PUFA) that share a final carbon-carbondouble bond in then−6 position, that is, the sixth bond, counting from themethyl end.[1] Health and medical organizations recommend intake of omega−6 fatty acids as part ofhealthful dietary patterns.[2][3][4]
TheAmerican Heart Association "supports an omega-6 PUFA intake of at least 5% to 10% of energy in the context of other AHA lifestyle and dietary recommendations. To reduce omega−6 PUFA intakes from their current levels would be more likely to increase than to decrease risk for coronary heart disease."[2]
A 2018 review found that an increased intake of omega−6 fatty acids reduces total serum cholesterol and may reducemyocardial infarction (heart attack), but found no significant change inLDL cholesterol andtriglycerides.[5] A 2021 review found that omega−6 supplements do not affect the risk ofCVD morbidity and mortality.[6]
A 2023 review found that omega−6 polyunsaturated fatty acids are associated with lower risk of highblood pressure.[7] Omega−6 fatty acids are not associated withatrial fibrillation.[8]
A review and meta-analysis of observational studies by theWorld Health Organization (WHO) found that higher intakes of omega−6 are associated with a 9% reduced risk ofall-cause mortality and a 31% increased risk of postmenopausal breast cancer.[9] The increased risk of breast cancer has not been confirmed in randomized controlled trials.[10]
A scoping review for Nordic Nutrition Recommendations 2023 found that partial replacement ofsaturated fatty acid with omega−6 fatty acid decreases risk of cardiovascular disease and improves the blood lipid profile.[4] A 2025 meta-analysis of 150 cohorts and meta-regression found that higher dietary intake and circulating levels of omega−6 fatty acids are associated with a lowered risk of cardiovascular disease, cancer and all-cause mortality.[11]
^Gunstone, Frank (December 2007)."Market update: Palm oil".International News on Fats, Oils and Related Materials.18 (12):835–36. Archived fromthe original on 2013-04-03.
^abc"FoodData Central". United States Department of Agriculture. 1 April 2019. All values in this table are from this database unless otherwise cited or when italicized as the simple arithmetic sum of other component columns.
^abcdKatragadda, Harinageswara Rao; Fullana, Andrés; Sidhu, Sukh; Carbonell-Barrachina, Ángel A. (May 2010). "Emissions of volatile aldehydes from heated cooking oils".Food Chemistry.120 (1):59–65.doi:10.1016/j.foodchem.2009.09.070.
^"Canola oil, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved6 September 2017.
^"Coconut oil, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved6 September 2017.
^"Palm oil, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved6 September 2017.
