Omega-6
At a glance
- Best for
- People with skin conditions (atopic dermatitis) or rheumatoid arthritis seeking GLA-rich oil adjuncts; general population rarely needs supplementation
- Typical dose
- Linoleic acid: 12–17 g/day from food; GLA supplements: 240–540 mg GLA/day
- Time to effect
- Weeks to months
- Main caution
- Most people already overconsume omega-6; supplementation should target specific GLA applications, not general omega-6 intake
What is it
Omega-6 fatty acids are polyunsaturated fatty acids characterized by a double bond at the sixth carbon from the methyl (omega) end of the chain. The parent molecule, linoleic acid (LA, 18:2 n-6) , is an essential nutrient that humans cannot synthesize; it is converted by delta-6 desaturase and elongase to gamma-linolenic acid (GLA, 18:3 n-6) , dihomo-gamma-linolenic acid (DGLA, 20:3 n-6) , and arachidonic acid (AA, 20:4 n-6) . These fatty acids are structural components of cell membranes and substrates for eicosanoid signaling: arachidonic acid is the precursor of pro-inflammatory prostaglandins (PGE2), leukotrienes (LTB4), and thromboxanes, while DGLA gives rise to anti-inflammatory PGE1. Supplemental omega-6 sources include borage oil, evening primrose oil, black currant seed oil (GLA-rich), and most seed oils (LA-rich).
Is it worth it for you?
Worth considering if…
- You have atopic dermatitis and want to try GLA-rich evening primrose or borage oil
- You have rheumatoid arthritis and are trying GLA as an adjunct
- You have confirmed essential fatty acid deficiency
Probably skip if…
- You eat a typical Western diet (you almost certainly already exceed adequate intake)
- You are on anticoagulants or have a bleeding disorder without medical guidance
- You are on phenothiazine antipsychotics or have a seizure disorder (borage and EPO may lower seizure threshold)
Evidence at a glance
| Goal | Evidence | Effect | Best fit | Time |
|---|---|---|---|---|
| essential fatty acid adequacy | Strong Evidence | Corrects EFA deficiency when LA intake meets adequate intake | People with fat malabsorption, very-low-fat diets, or prolonged fat-free parenteral nutrition | Weeks |
| cardiovascular risk reduction via saturated fat replacement | Good Evidence | ~10–15% LDL reduction when LA-rich oils replace saturated fat in diet | Adults replacing saturated fat sources with polyunsaturated vegetable oils | Weeks to months for lipid changes |
| atopic dermatitis with GLA-rich oils | Mixed Evidence | Modest reduction in itch and skin severity scores in some trials; inconsistent | Adults and children with mild-to-moderate atopic dermatitis | 8–16 weeks |
Evidence for 3 uses
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
essential fatty acid adequacy
Corrects deficiencyLinoleic acid (the parent omega-6) is a dietary essential fatty acid required for membrane phospholipids, skin barrier integrity, and arachidonic acid production. True EFA deficiency is rare in any diet containing vegetable oils and manifests as scaly dermatitis, growth failure, and reproductive problems. The AI of 12–17 g/day is easily met through normal food.
Bottom line: Meeting adequate omega-6 intake prevents EFA deficiency; supplementation is not needed in typical diets.
cardiovascular risk reduction via saturated fat replacement
Supplement benefitMeta-analyses show that replacing saturated fat with linoleic acid-rich polyunsaturated oils reduces LDL cholesterol and lowers coronary heart disease risk. This is a dietary exchange effect, not a standalone supplement effect. Adding more omega-6 without reducing saturated fat provides much less benefit.
Bottom line: Replacing saturated fat with LA-rich vegetable oils is a dietary strategy with B-level evidence; isolated omega-6 supplementation is not.
atopic dermatitis with GLA-rich oils
Supplement benefitGLA (gamma-linolenic acid) from evening primrose oil or borage oil is proposed to correct an impaired delta-6-desaturase step in atopic dermatitis. Some RCTs show modest improvement in itch, erythema, and scaling scores; larger, better-controlled trials are often neutral. Cochrane reviews give a tentative finding of possible modest benefit that is not robust across all trials.
Bottom line: GLA-rich oils may modestly improve atopic dermatitis symptoms; evidence is inconsistent and effect sizes are small.
Evidence is mixed
Early trials were positive; later and larger RCTs and Cochrane analyses found effects that were modest and heterogeneous, limiting confidence.
How to take it
- Typical dose
- For GLA: evening primrose oil 3–6 g/day (~270–540 mg GLA) or borage oil 1–3 g/day (~200–600 mg GLA)
- Timing
- With meals for best absorption
- With food
- With food; fat-containing meals improve absorption
- How long to try
- Trial 8–24 weeks for atopic dermatitis or RA before judging response
What to track
- Skin symptoms or eczema severity
- Joint pain and swelling if used for RA
- Any unusual bruising or bleeding
- GI tolerance
Safety
Common side effects
GI upset, soft stools, belching with borage or evening primrose oil, Mild bloating
Serious risks
- Borage oil may contain pyrrolizidine alkaloids (hepatotoxic) if not certified PA-free
- Evening primrose and borage oil may lower seizure threshold in susceptible individuals
Who should avoid it
- People with epilepsy or on phenothiazines
- People on warfarin or DOACs without medical guidance
- Pre-surgical patients (discontinue 1–2 weeks before surgery)
Pregnancy & breastfeeding
Dietary omega-6 from food is safe in pregnancy; high-dose GLA supplements (borage, EPO) have insufficient safety data and should be avoided unless specifically recommended by a provider.
Interactions
High-dose GLA oils modestly prolong bleeding time; monitor INR and inform prescriber
Evening primrose and borage oils may lower seizure threshold in combination
Additive antiplatelet effect; flag before surgery
Choosing a product
Look for
- GLA content stated in mg per dose (not just oil weight)
- PA-free certification for borage oil
- Third-party tested for heavy metals and purity
Be skeptical of
- Anti-inflammatory omega-6
- Balances your omega-3:6 ratio (supplementation raises omega-6 further)
- Treats eczema or arthritis definitively
References by claim
Track Omega-6 with Pilora
Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.
Coming to App StoreDisclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.