Omega-6

Omega-6 fatty acids are essential polyunsaturated fats that the body cannot make. The main one, linoleic acid, comes from vegetable oils, nuts and seeds. Eaten in place of saturated fat, they help lower LDL cholesterol.

What is it?

The main omega-6 fat in the diet is linoleic acid (LA). The body can convert it into arachidonic acid (AA), which is used to make signalling molecules (eicosanoids) that help control inflammation, blood clotting and blood vessels. A smaller amount of omega-6 comes as GLA from evening primrose and borage oil.

What it does

1. Is needed for healthy skin, hair and growth
2. Is a building block for cell membranes
3. Lowers LDL cholesterol when it replaces saturated fat
4. Is converted into signalling molecules for immunity, inflammation and blood vessels

Food sources

Sunflower, safflower, corn and soybean oil, walnuts, sunflower seeds, pumpkin seeds, sesame seeds, tofu, eggs and poultry. Many processed and fried foods are high in omega-6 because they are made with these oils.

Singapore food examples

1. Sunflower, corn and soybean oil in cooking and dressings
2. Walnuts, sunflower and pumpkin seeds
3. Sesame seeds and sesame oil
4. Tofu and tempeh
5. Eggs and chicken

How much do I need?

Singapore's RDA table does not list omega-6. The US National Academies set an Adequate Intake for linoleic acid of 17 g a day for men and 12 g for women aged 19 to 50 (14 g and 11 g after 50), and advise 5 to 10 percent of energy from omega-6. See Singapore's dietary guidelines for adults (HealthHub) for Singapore's overall fat guidance.

Low intake and deficiency

Deficiency is rare in adults. It causes dry, scaly skin, hair loss, poor wound healing and, in infants, poor growth. It can occur with severe fat malabsorption or with long-term intravenous feeding without lipids.

Too much and safety

Replacing saturated fat with omega-6 oils lowers heart disease risk, and moderate intake is considered safe. Some people worry that omega-6 promotes inflammation; for most people, studies do not show higher inflammatory markers with higher intakes, but very high intakes relative to omega-3 are not recommended. Omega-6 oils are fragile — repeated deep frying produces harmful compounds.

Absorption and bioavailability

Absorbed efficiently with other fat. The body converts linoleic acid to arachidonic acid, and competes for the same enzymes as omega-3, which is why a balance matters. Eat more fish or omega-3 sources if your diet is rich in omega-6 oils.

Connection to daily life

1. Heart health: choose plant oils over butter and ghee for everyday cooking
2. Skin health: essential fats keep the skin barrier intact
3. Balance: pair omega-6 oils with fish, walnuts and flaxseed for omega-3 — see Omega-3

Sources: 1. National Academies of Sciences, Engineering, and Medicine — Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2005) 2. HealthHub Singapore — Recommended Dietary Allowances: https://www.healthhub.sg/well-being-and-lifestyle/food-diet-and-nutrition/recommended_dietary_allowances 3. HealthHub Singapore — Dietary guidelines for adults: https://www.healthhub.sg/well-being-and-lifestyle/food-diet-and-nutrition/dietary_guidelines_adults 4. Health Promotion Board — Singapore Food Insights Database (SG FoodID): https://www.hpb.gov.sg/healthy-living/food-and-beverage/sgfoodid/ 5. FAO/INFOODS — Food composition tables and databases: https://www.fao.org/food-composition/tables-and-databases/en/