Seed Oils: Omega-6, Omega-3 and Health: Striking the Right Balance
- Alastair Hunt
- 19 hours ago
- 6 min read
Updated: 2 hours ago
Part 6 of the Seed Oils Series
Another concern raised about seed oils focuses on their contribution to an imbalanced intake of omega-6 and omega-3 fatty acids. It is often claimed that our modern diets, rich in seed oils, provide too much omega-6 relative to omega-3, promoting inflammation and chronic disease. But what does the evidence actually say?
Omega-6 and omega-3 fats are both essential; the body cannot produce them and must obtain them from the diet. Linoleic acid (omega-6) is the most abundant polyunsaturated fat in seed oils, while alpha-linolenic acid (ALA, an omega-3) is found in flaxseeds, chia seeds, walnuts and canola oil. The long-chain omega-3s, EPA and DHA, primarily come from marine sources like oily fish and algae.
While it is true that the traditional Western diet has a higher omega-6:omega-3 ratio than historical patterns, the bigger issue appears to be a deficiency of omega-3 rather than harmful excess of omega-6. Multiple meta-analyses, including Abdelhamid et al. (2018, Cochrane Review), suggest that increasing omega-3 intake, particularly from marine sources, improves cardiovascular outcomes without requiring a dramatic reduction in omega-6 intake.
Modern research has challenged the idea that omega-6 fats are pro-inflammatory in humans. As discussed earlier, linoleic acid does not raise inflammatory markers in clinical trials and higher blood levels of linoleic acid are associated with lower risks of heart disease, stroke and overall mortality. See links to supporting studies at Bottom of Page.
The solution is not to fear seed oils but to ensure adequate omega-3
And here is how:
Eating oily fish (such as salmon, mackerel, sardines) two to three times per week.
Adding walnuts, chia seeds, and flaxseeds to meals regularly.
Considering a high-quality fish oil or algae oil supplement, particularly for individuals with low fish consumption.
At the same time, reducing reliance on highly processed foods - which often combine seed oils with refined starches and sugars - remains a cornerstone of better dietary patterns. In this way, seed oils can be part of a balanced, health-promoting diet without dominating it.
Individual fat needs vary. People with inflammatory conditions, bleeding disorders or specific cardiovascular risks should consult their healthcare provider before making substantial changes to fat intake or starting omega-3 supplementation. Dietary advice must always be tailored to personal health contexts.
A healthy balance comes not from eliminating omega-6 fats but from improving omega-3 intake and focusing on whole, minimally processed foods.
Return to Part 1: Seed Oils, An Introduction
Final Thoughts
While seed oils can be a divisive issue online, we are relatively agnostic when it come to diet and eating patterns. If you enjoy cooking with olive oil or avocado oil - rather than a seed oil - we do too. But we are not concerned about a splash of canola in our stir fry and we try to avoid ultra-processed foods as part of our daily eating.
Changing health for the better is about progress, not perfection, and even small changes can make a meaningful difference over time. For most people, improving health is about finding motivation and prioritising self-care - with an ultimate goal of taking action. If you want to take effective and targeted steps that fit into your unique lifestyle and circumstances, The Whole Health Practice is here to help.
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Alastair
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Grytten E, Laupsa-Borge J, Cetin K, Bohov P, Nordrehaug JE, Skorve J, Berge RK, Strand E, Bjørndal B, Nygård OK, Rostrup E, Mellgren G, Dankel SN. Inflammatory markers after supplementation with marine n-3 or plant n-6 PUFAs: A randomized double-blind crossover study. J Lipid Res. 2025 Mar 8;66(4):100770. doi: 10.1016/j.jlr.2025.100770. Epub ahead of print. PMID: 40058591; PMCID: PMC11999210.
Zhang Y, Sun Y, Yu Q, Song S, Brenna JT, Shen Y, Ye K. Higher ratio of plasma omega-6/omega-3 fatty acids is associated with greater risk of all-cause, cancer, and cardiovascular mortality: A population-based cohort study in UK Biobank. Elife. 2024 Apr 5;12:RP90132. doi: 10.7554/eLife.90132. PMID: 38578269; PMCID: PMC10997328.
Jackson KH, Harris WS, Belury MA, Kris-Etherton PM, Calder PC. Beneficial effects of linoleic acid on cardiometabolic health: an update. Lipids Health Dis. 2024 Sep 12;23(1):296. doi: 10.1186/s12944-024-02246-2. PMID: 39267068; PMCID: PMC11391774.
Li Y, Tang H, Yang X, Ma L, Zhou H, Zhang G, Chen X, Ma L, Gao J, Ji W. Associations of ω-3, ω-6 polyunsaturated fatty acids intake and ω-6: ω-3 ratio with systemic immune and inflammatory biomarkers: NHANES 1999-2020. Front Nutr. 2024 Jun 7;11:1410154. doi: 10.3389/fnut.2024.1410154. PMID: 38912301; PMCID: PMC11190316.
Wang Q, Zhang H, Jin Q, Wang X. Effects of Dietary Linoleic Acid on Blood Lipid Profiles: A Systematic Review and Meta-Analysis of 40 Randomized Controlled Trials. Foods. 2023 May 25;12(11):2129. doi: 10.3390/foods12112129. PMID: 37297374; PMCID: PMC10253160.
Dyall SC, Balas L, Bazan NG, Brenna JT, Chiang N, da Costa Souza F, Dalli J, Durand T, Galano JM, Lein PJ, Serhan CN, Taha AY. Polyunsaturated fatty acids and fatty acid-derived lipid mediators: Recent advances in the understanding of their biosynthesis, structures, and functions. Prog Lipid Res. 2022 Apr;86:101165. doi: 10.1016/j.plipres.2022.101165. Epub 2022 May 1. PMID: 35508275; PMCID: PMC9346631.
Grosso G, Laudisio D, Frias-Toral E, Barrea L, Muscogiuri G, Savastano S, Colao A. Anti-Inflammatory Nutrients and Obesity-Associated Metabolic-Inflammation: State of the Art and Future Direction. Nutrients. 2022 Mar 8;14(6):1137. doi: 10.3390/nu14061137. PMID: 35334794; PMCID: PMC8954840.
Li J, Guasch-Ferré M, Li Y, Hu FB. Dietary intake and biomarkers of linoleic acid and mortality: systematic review and meta-analysis of prospective cohort studies. Am J Clin Nutr. 2020 Jul 1;112(1):150-167. doi: 10.1093/ajcn/nqz349. PMID: 32020162; PMCID: PMC7326588.
Marangoni F, Agostoni C, Borghi C, Catapano AL, Cena H, Ghiselli A, La Vecchia C, Lercker G, Manzato E, Pirillo A, Riccardi G, Risé P, Visioli F, Poli A. Dietary linoleic acid and human health: Focus on cardiovascular and cardiometabolic effects. Atherosclerosis. 2020 Jan;292:90-98. doi: 10.1016/j.atherosclerosis.2019.11.018. Epub 2019 Nov 15. PMID: 31785494.
Abdelhamid AS, Brown TJ, Brainard JS, Biswas P, Thorpe GC, Moore HJ, Deane KH, Summerbell CD, Worthington HV, Song F, Hooper L. Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database Syst Rev. 2020 Feb 29;3(3):CD003177. doi: 10.1002/14651858.CD003177.pub5. PMID: 32114706; PMCID: PMC7049091.
Abdelhamid AS, Brown TJ, Brainard JS, Biswas P, Thorpe GC, Moore HJ, Deane KH, AlAbdulghafoor FK, Summerbell CD, Worthington HV, Song F, Hooper L. Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database Syst Rev. 2018 Nov 30;11(11):CD003177. doi: 10.1002/14651858.CD003177.pub4. Update in: Cochrane Database Syst Rev. 2020 Feb 29;3:CD003177. doi: 10.1002/14651858.CD003177.pub5. PMID: 30521670; PMCID: PMC6517311.
Innes JK, Calder PC. Omega-6 fatty acids and inflammation. Prostaglandins Leukot Essent Fatty Acids. 2018 May;132:41-48. doi: 10.1016/j.plefa.2018.03.004. Epub 2018 Mar 22. PMID: 29610056.
Su H, Liu R, Chang M, Huang J, Wang X. Dietary linoleic acid intake and blood inflammatory markers: a systematic review and meta-analysis of randomized controlled trials. Food Funct. 2017 Sep 20;8(9):3091-3103. doi: 10.1039/c7fo00433h. PMID: 28752873.
Farvid MS, Ding M, Pan A, Sun Q, Chiuve SE, Steffen LM, Willett WC, Hu FB. Dietary linoleic acid and risk of coronary heart disease: a systematic review and meta-analysis of prospective cohort studies. Circulation. 2014 Oct 28;130(18):1568-78. doi: 10.1161/CIRCULATIONAHA.114.010236. Epub 2014 Aug 26. PMID: 25161045; PMCID: PMC4334131.
Rett BS, Whelan J. Increasing dietary linoleic acid does not increase tissue arachidonic acid content in adults consuming Western-type diets: a systematic review. Nutr Metab (Lond). 2011 Jun 10;8:36. doi: 10.1186/1743-7075-8-36. PMID: 21663641; PMCID: PMC3132704.
Hussein N, Ah-Sing E, Wilkinson P, Leach C, Griffin BA, Millward DJ. Long-chain conversion of [13C]linoleic acid and alpha-linolenic acid in response to marked changes in their dietary intake in men. J Lipid Res. 2005 Feb;46(2):269-80. doi: 10.1194/jlr.M400225-JLR200. Epub 2004 Dec 1. PMID: 15576848.
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