Omega-6 Fatty Acids
Summary
Eating more omega-6 fat lowers total cholesterol a little (high-quality evidence, 10 trials, 4,280 people) but made little or no difference to deaths or heart events in a Cochrane review of 19 trials. The AHA supports getting at least 5% to 10% of energy from omega-6.
Key facts
- Polyunsaturated fats; linoleic acid is the main dietary omega-6 and must come from food[3]
- 17 g/day of linoleic acid for men and 12 g/day for women aged 19 to 50 (Institute of Medicine, cited by the AHA)[3]
- Total cholesterol (lowered, B); deaths and heart events (little or no difference, C)[1]
- Three AHA advisory authors disclosed industry ties: the chair, William Harris (Monsanto research grant; consulting for Monsanto and Unilever), Penny Kris-Etherton (California Walnut Commission research support and consulting; Unilever consulting) and Dariush Mozaffarian (research grants from GSK, Sigma-Tau and Pronova); the Cochrane update was funded by WHO[3][1]
- 3 graded human outcomes on this page
- October 10, 2026
How it works
EstablishedLinoleic acid lowers LDL cholesterol when it replaces saturated fat. It can be converted to arachidonic acid, but conversion is tightly regulated (about 0.2% in tracer studies), so dietary changes barely alter tissue arachidonic acid.[3]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Blood lipids | Grade B | Improved | Meta-analysis · n = 4,280 · 2018 | 2 rows |
| Heart outcomes | Grade C | No effect | Meta-analysis · n = 4,506 · 2018 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Total cholesterol | Improved | Grade B | Meta-analysis · n = 4,280 · 2018 Adults with or without cardiovascular disease (10 trials) Form: Higher omega-6 intake (linoleic acid or GLA), usually replacing saturated or monounsaturated fat · Dose: Varied across trials · Duration: At least 12 months Total cholesterol fell by 0.33 mmol/L (high-quality evidence; heterogeneity partly explained by dose). Triglycerides, HDL and LDL showed little or no difference in fewer trials. | 30488422 (opens PubMed)Source [1] |
| All-cause mortality and cardiovascular events | No effect | Grade C | Meta-analysis · n = 4,506 · 2018 Adults with or without cardiovascular disease (10 trials for mortality) Form: Higher omega-6 intake (12 linoleic acid trials, 7 GLA supplement trials in the review) · Dose: Varied across trials · Duration: 1 to 8 years Little or no difference in all-cause mortality (RR 1.00) or cardiovascular events (RR 0.97, 7 trials, 4,962 people), based on low-quality evidence. Heart attack risk may be slightly lower (RR 0.88, 95% CI 0.76 to 1.02). | 30488422 (opens PubMed)Source [1] |
| Lipoprotein(a) | Improved | Grade D | RCT · n = 118 · 2024 Men homozygous for a FADS1 gene variant (Finland) Form: Sunflower oil (linoleic acid) compared with camelina oil (alpha-linolenic acid) · Dose: 30 to 50 mL oil per day, by body size · Duration: 8 weeks The linoleic acid diet lowered Lp(a) by 9.5% and the ALA diet by 7.3%, with no significant difference between diets; LDL cholesterol and apolipoprotein B fell more on the ALA diet. | 38714425 (opens PubMed)Source [2] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Linoleic acid from vegetable oils | Varies[1][2][3] | Linoleic acid is the main dietary omega-6; about 0.2% is converted to arachidonic acid in tracer studies.[3] | No adverse events attributed in the abstracts cited here.[2] | Diet trials replacing saturated or monounsaturated fat |
| Gamma-linolenic acid (GLA) supplements | Varies[1] | No absorption data in our sources.[1] | Not reported separately in the abstract.[1] | Seven GLA supplement trials in the Cochrane review |
Studied doses
Doses studied in human trials ranged from 30 to 50 mL of sunflower oil per day for 8 weeks to diets supplying 11% to 21% of energy from omega-6 fat in older diet-heart trials; trials in the Cochrane review lasted 1 to 8 years.[2][3][1]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
Other supplements
- Omega-3 fatsReviewHigher omega-6 intake can inhibit conversion of alpha-linolenic acid to EPA, but that conversion is already low and the AHA judges the net effect on heart risk unclear.[3]
Who should be careful
- People expecting supplements to lower heart risk
- The Cochrane review found little or no difference in deaths or cardiovascular events with more omega-6.[1]
- Pregnancy, breastfeeding and children
- The trials cited here studied adults; GLA supplement safety in these groups is not covered by our sources.[1]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Safety
Omega-6 fats are essential nutrients; the debate is about how much, not whether, to eat them.
- Trial quality
- Only 3 of the 19 trials in the Cochrane review were at low summary risk of bias.[1]
- Pooled trials
- Across 19 trials there was little or no difference in deaths or cardiovascular events.[1]
- Expert position
- The AHA advisory judged intakes of at least 5% to 10% of energy safe and potentially beneficial for heart risk.[3]
How to read the label
- Food firstMost omega-6 comes from cooking oils, nuts and seeds; average US intake was 14.8 g/day of linoleic acid (NHANES 2001 to 2002).[3]
- GLA productsSupplements sold as omega-6 usually contain GLA; seven GLA trials were included in the Cochrane review.[1]
- RatiosThe AHA calls the focus on omega-6 to omega-3 ratios conceptually limited and prefers looking at intake of each fat.[3]
Frequently asked questions
Are omega-6 fats bad for you?
Linoleic acid is essential. A Cochrane review of 19 trials found more omega-6 made little or no difference to deaths and lowered total cholesterol a little.[1]
How much omega-6 do adults need?
The Institute of Medicine adequate intake is 17 g/day of linoleic acid for men and 12 g/day for women aged 19 to 50, about the median US intake.[3]
Does omega-6 cause inflammation?
The AHA advisory found little direct evidence of a net pro-inflammatory effect of linoleic acid in humans, partly because little is converted to arachidonic acid.[3]
Do I need an omega-6 supplement?
Most people get omega-6 from vegetable oils, nuts and seeds; average US linoleic acid intake was about 14.8 g/day.[3]
Sources
- [1]Omega-6 fats for the primary and secondary prevention of cardiovascular disease.. Cochrane Database Syst Rev, 2018. meta-analysis
- [2]Dietary n-3 alpha-linolenic and n-6 linoleic acids modestly lower serum lipoprotein(a) concentration but differentially influence other atherogenic lipoprotein traits: A randomized trial.. Atherosclerosis, 2024. RCT
- [3]Omega-6 fatty acids and risk for cardiovascular disease: a science advisory from the American Heart Association Nutrition Subcommittee of the Council on Nutrition, Physical Activity, and Metabolism; Council on Cardiovascular Nursing; and Council on Epidemiology and Prevention.. Circulation, 2009. guideline
What changed
- First draft. Every PMID checked against NCBI E-utilities esummary (title and year taken from the record) and abstracts read for the cited rows.
- Adversarial review pass: every evidence row re-read against its whole PubMed abstract. Official source opened: AHA science advisory on omega-6 fatty acids (Circulation 2009, PMID 19171857, full text on ahajournals.org) for the Institute of Medicine adequate intake and the AHA position; no NIH ODS or NCCIH fact sheet covers omega-6 fats. Excluded: Sydney Diet Heart Study recovered-data analysis (23386268) because PubMed lists an erratum. Superseded Cochrane versions excluded (26571451, 30019765 -> current 30488422, no further UpdateIn). Industry ties: AHA writing-group disclosures include Monsanto, Unilever and California Walnut Commission; the Cochrane update was funded by WHO; Retraction, expression-of-concern, erratum and withdrawn checks on all cited PMIDs: none flagged. Page set indexable.