Reference articles on history, science, culture and more
Encyclopedia

Omega−6 fatty acid

Fatty acids where the sixth bond is double

Image credit is listed at the end of this article.

Omega−6 fatty acids (also referred to as ω−6 fatty acids or n−6 fatty acids) are a family of essential polyunsaturated fatty acids (PUFA) that share a final carbon-carbon double bond in the n−6 position, that is, the sixth bond, counting from the methyl end. Health and medical organizations recommend intake of omega−6 fatty acids as part of healthful dietary patterns.

01Health effects

The American 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."

A 2018 review found that an increased intake of omega−6 fatty acids reduces total serum cholesterol and may reduce myocardial infarction (heart attack), but found no significant change in LDL cholesterol and triglycerides. A 2021 review found that omega−6 supplements do not affect the risk of CVD morbidity and mortality.

A 2023 review found that omega−6 polyunsaturated fatty acids are associated with lower risk of high blood pressure. Omega−6 fatty acids are not associated with atrial fibrillation.

A review and meta-analysis of observational studies by the World Health Organization (WHO) found that higher intakes of omega−6 are associated with a 9% reduced risk of all-cause mortality and a 31% increased risk of postmenopausal breast cancer. The increased risk of breast cancer has not been confirmed in randomized controlled trials.

A scoping review for Nordic Nutrition Recommendations 2023 found that partial replacement of saturated fatty acid with omega−6 fatty acid decreases risk of cardiovascular disease and improves the blood lipid profile. 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.

Comparison of dietary fat composition from a 1995 study.
Comparison of dietary fat composition from a 1995 study.

02Dietary sources

Dietary sources of omega−6 fatty acids include:

Vegetable oils

Vegetable oils are a major source of omega−6 linoleic acid. Worldwide, more than 100 million metric tons of vegetable oils are extracted annually from palm fruits, soybean seeds, grape seeds, and sunflower seeds, providing more than 32 million metric tons of omega−6 linoleic acid and 4 million metric tons of omega−3 alpha-linolenic acid.

Properties of vegetable oils
The nutritional values are expressed as percent (%) by mass of total fat.
TypeProcessing
treatment
Saturated
fatty acids
Monounsaturated
fatty acids
Polyunsaturated
fatty acids
Smoke point
TotalOleic
acid
(ω−9)
Totalα-Linolenic
acid
(ω−3)
Linoleic
acid
(ω−6)
ω−6:3
ratio
Avocado11.670.667.913.5112.512.5:1250 °C (482 °F)
Brazil nut17.626.726.155.70.155.6457:1208 °C (406 °F)
Canola7.463.361.828.19.118.62:1204 °C (400 °F)
Coconut82.56.361.70.0191.6888:1175 °C (347 °F)
Corn12.927.627.354.715858:1232 °C (450 °F)
Cottonseed25.917.81951.915454:1216 °C (420 °F)
Cottonseedhydrogenated93.61.50.60.20.31.5:1
Flaxseed/linseed9.018.41867.853130.2:1107 °C (225 °F)
Grape seed 9.616.115.8  69.90.1069.6very high216 °C (421 °F)
Hemp seed7.09.09.082.022.054.02.5:1166 °C (330 °F)
High-oleic safflower oil7.575.275.212.8012.8very high212 °C (414 °F)
Olive (extra virgin)13.873.071.310.50.79.814:1193 °C (380 °F)
Palm49.337.0409.30.29.145.5:1235 °C (455 °F)
Palmhydrogenated88.25.70
Peanut16.257.155.419.90.31819.661.6:1232 °C (450 °F)
Rice bran oil2538.438.436.62.234.415.6:1232 °C (450 °F)
Sesame14.239.739.341.70.341.3138:1
Soybean15.622.822.657.77517.3:1238 °C (460 °F)
Soybeanpartially hydrogenated14.943.042.537.62.634.913.4:1
Sunflower oil8.9963.462.920.70.1620.5128:1227 °C (440 °F)
Walnut oilunrefined9.122.822.263.310.452.95:1160 °C (320 °F)
The chemical structure of linoleic acid, a common omega−6 fatty acid found in many nuts, seeds, and vegetable oils.
The chemical structure of linoleic acid, a common omega−6 fatty acid found in many nuts, seeds, and vegetable oils.

03List of omega−6 fatty acids

Common name Lipid name Chemical name
Linoleic acid (LA) 18:2 (n−6) all-cis-9,12-octadecadienoic acid
Gamma-linolenic acid (GLA) 18:3 (n−6) all-cis-6,9,12-octadecatrienoic acid
Calendic acid 18:3 (n−6) 8E,10E,12Z-octadecatrienoic acid
Eicosadienoic acid 20:2 (n−6) all-cis-11,14-eicosadienoic acid
Dihomo-gamma-linolenic acid (DGLA) 20:3 (n−6) all-cis-8,11,14-eicosatrienoic acid
Arachidonic acid (AA, ARA) 20:4 (n−6) all-cis-5,8,11,14-eicosatetraenoic acid
Docosadienoic acid 22:2 (n−6) all-cis-13,16-docosadienoic acid
Adrenic acid 22:4 (n−6) all-cis-7,10,13,16-docosatetraenoic acid
Osbond acid 22:5 (n−6) all-cis-4,7,10,13,16-docosapentaenoic acid
Tetracosatetraenoic acid 24:4 (n−6) all-cis-9,12,15,18-tetracosatetraenoic acid
Tetracosapentaenoic acid 24:5 (n−6) all-cis-6,9,12,15,18-tetracosapentaenoic acid

The melting point of the fatty acids increases as the number of carbons in the chain increases.

Watch videos about Omega−6 fatty acidExplainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article Omega−6 fatty acid, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

Images, from Wikimedia Commons:

Fathomly is not affiliated with or endorsed by the Wikimedia Foundation. Spotted a problem? Tell us.