Are seed oils bad for your heart?
Short answer
Not clearly; the evidence conflicts.
One 1966-73 trial found more deaths when men swapped saturated fat for safflower oil. Pooled trials, population studies and short diet trials found no clear harm. The evidence is thin and conflicting.
This page says what the research shows. It does not say whether you should use seed oils.
Where the evidence stands
Each dot is one on-topic paper. Steps near the top answer the question more directly. Select a dot to see the study.
↑ Stronger evidence
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Trials in people: heart disease
Trials that measured heart disease and inflammation directly.
1 -
Trials in people: other measures
Trials that measured other health or performance measures.
0None among the papers we read.
-
Trials in people: lab tests or safety
Trials that measured lab tests, side effects or safety.
4 -
Population studies
Studies that followed or surveyed groups of people. They show links, not causes.
2 -
Blood levels and genes
Studies that link blood levels or genes to health.
0None among the papers we read.
↓ Weaker evidence
- Points to benefit
- Mixed
- No difference
- No direction
- Points to harm
Not on the ladder: 3 reviews of many studies (shown below), 3 opinion or narrative papers. Counts are papers, not people. Some studies appear in more than one paper.
See every studyWhat we found
- In a 1966-73 trial of 458 men with a recent heart event, those told to swap saturated fat for safflower oil died more often (17.6% v 11.8%). Ramsden 2013
- A review of 15 trials found cutting saturated fat lowered combined heart and blood vessel events by 21%; replacing it with polyunsaturated fat looked as useful as carbohydrate. Hooper 2020
- In two diet trials of 8 and 10 weeks, oils rich in omega-6 did not raise inflammation markers, compared with olive oil or with butter. Prater 2024, Bjermo 2012
- Among 135 335 adults in 18 countries, those eating the most polyunsaturated fat had fewer deaths overall (HR 0·80), but no link to heart attacks or heart deaths. Dehghan 2017
What the research says
An old safflower oil trial found more deaths
The Sydney Diet Heart Study ran in 1966-73 with 458 men who had a recent heart event. Men told to swap saturated fat for safflower oil and safflower margarine died more often: 17.6% v 11.8% from any cause, and 16.3% v 10.1% from coronary heart disease.
These data were recovered and reported in 2013. Added to other linoleic acid trials, the pooled result leaned toward more heart deaths (hazard ratio 1.33), but its range (0.99 to 1.79) included no effect. The authors found no sign of heart benefit.
Studies: Ramsden 2013
Cutting saturated fat lowered heart events in pooled trials
A Cochrane review pooled 15 trials with about 59,000 people. Cutting saturated fat for at least two years lowered combined heart and blood vessel events by 21% (RR 0.79). Swapping in polyunsaturated fat or carbohydrate looked about equally useful. Deaths from any cause barely changed (RR 0.96).
This review gives no separate number for polyunsaturated fat and does not name seed oils, so it answers a broader question. It and the Sydney trial point in opposite directions.
Studies: Hooper 2020, Ramsden 2013
Omega-6 diets did not raise inflammation in trials
In 42 adults with high cholesterol, 8 weeks of meals rich in cottonseed oil versus olive oil showed no difference in C-reactive protein (P = 0.70) or other inflammation markers. In 61 adults with belly fat, a 10-week omega-6 diet lowered some inflammation markers compared with butter.
Population data are less tidy. In two UK cohorts, total omega-6 went with higher GlycA, an inflammation marker, but so did omega-3. The authors found no simple split between inflammatory omega-6 and anti-inflammatory omega-3. These links do not show cause.
Studies: Prater 2024, Bjermo 2012, Crick 2025
Heart risk markers: small differences between oils
Ninety Chinese women at high heart risk cooked with soybean, olive or camellia seed oil for 3 months. Weight did not differ. Olive oil raised HDL cholesterol slightly more than soybean oil (P = 0.03), and the authors judged the olive and camellia oils more favorable.
An umbrella review of 48 studies found canola oil lowered total and LDL cholesterol, with moderate to very low certainty. A pooled analysis of 884 trials listed omega-6 supplements among those lowering heart risk factors. A 4-week hemp trial found no differences in blood fats or blood pressure.
Reviews of population studies lean toward benefit
Three narrative reviews say higher linoleic acid or omega-6 intake goes with lower heart disease risk, mostly from long-term population studies. One says higher blood linoleic acid goes with lower risk of coronary heart disease, stroke and type 2 diabetes.
These are narrative reviews, not systematic ones, and two have authors with company ties (OmegaQuant, United Soybean Board, DSM, BASF, Cargill). Population studies show links, not causes. The large PURE study found no link between polyunsaturated fat and heart attacks or heart deaths.
Studies: Wang 2018, Jackson 2024, Djuricic 2021, Dehghan 2017
What reviews of many studies found
Reviews pool or sum up earlier studies. They are not on the ladder, because they repeat studies already counted there.
Pooled review (meta-analysis) · Hooper 2020
Pooled 15 trials (about 59,000 people) of cutting saturated fat for at least two years. Combined heart and blood vessel events fell 21% (RR 0.79). Swapping in polyunsaturated fat or carbohydrate looked useful; no separate polyunsaturated fat number.
Pooled review (meta-analysis) · An 2022
Pooled 884 trials of 27 supplements with 883,627 people. Omega-6 fatty acid supplements were among those with moderate- to high-quality evidence for lowering heart risk factors. The abstract gives no omega-6 numbers or heart-event results.
Systematic review · Voon 2024
Umbrella review of 48 studies, including 206 meta-analyses, on vegetable oils in adults. Canola, virgin olive and rice bran oils lowered total and LDL cholesterol, with moderate to very low certainty. The abstract reports no heart attacks or heart deaths.
How the research grew
The papers we read span 2012 to 2026. 5 of the 13 on-topic papers came out in 2024 to 2026. The earliest trial in people here is from 2012.
- 2012
- 2013
- 2017
- 2018
- 2020
- 2021
- 2022
- 2024
- 2025
- 2026
Each dot is one on-topic paper, colored by what it found. Rings mark key papers:
- 2012. Trial: omega-6 diet did not raise inflammation. Bjermo 2012
- 2013. Recovered 1966-73 trial linked safflower oil to more deaths. Ramsden 2013
- 2017. PURE: 135 335 adults followed in 18 countries. Dehghan 2017
- 2020. Cochrane review of 15 saturated fat trials. Hooper 2020
- 2022. Biggest pooled review: 884 supplement trials. An 2022
Who was studied
Who took part, and how many. The largest trial here had 458 people; the largest population study had 135,335.
- Trials in people
- Population, blood and gene studies
- People in the study, log scale1101001,00010,000100,0001,000,000
- Points to benefit
- Mixed
- No difference
- No direction
- Points to harm
Bars use a log scale: each step is ten times more people. Reviews, animal studies and papers with no count in the abstract are not shown.
Who funds this research
None of the 5 trial papers shows a company stake; 4 have no disclosure in PubMed. Company ties appear in two narrative reviews (OmegaQuant, United Soybean Board; DSM, BASF, Cargill) and one pooled review (Abbott Nutrition). They did not change the confidence.
- No disclosure in PubMed 4
- No stake declared 1
- Prater 2024No disclosure in PubMed
- Wu 2022No disclosure in PubMed
- She 2026No disclosure in PubMed
- Bjermo 2012No disclosure in PubMed
- Ramsden 2013No stake declared
Funding rule. A stake is always shown. Confidence is lowered only when every supporting study comes from a party with a stake. "No disclosure in PubMed" means the PubMed record has no conflict-of-interest statement. It does not mean there is no conflict.
All 13 on-topic papers
Each paper shows what it tested, what it found, and who has a stake. Every paper also has its own page that explains how much it counts and how it fits. See every study as a list.
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Randomized trial · measured the question itselfRamsden et al., 2013BMJ (Clinical research ed.) · PubMed
Use of dietary linoleic acid for secondary prevention of coronary heart disease and death: evaluation of recovered data from the Sydney Diet Heart Study and updated meta-analysis.
458 people · men aged 30 to 59 who had a recent heart event
TestedSafflower oil and safflower margarine (high linoleic acid) instead of saturated fat, vs usual diet
Swapping saturated fat for safflower oil led to more deaths: all causes 17.6% v 11.8% (hazard ratio 1.62), coronary heart disease 16.3% v 10.1% (1.74). Pooled with other trials, heart deaths leaned higher, but not clearly (1.33; 0.99 to 1.79).
Points to harmNo stake declaredAbstract onlyFunded by a life insurance research fund and NIH; no ties to oil or food companies declared.
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The effect of hemp product consumption on blood fatty acid profiles and cardiovascular disease risk factors: results of a randomized, double-blind, crossover clinical trial.
30 people · adults aged 18 to 65 who were overweight, with normal blood sugar
TestedHemp seeds and hemp oil (rich in omega-6 and omega-3) vs similar control foods, 4 weeks each
Hemp raised blood levels of the fats it contains. No differences in blood fats, sugar, insulin, blood pressure or body makeup.
No differenceNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Randomized trial · lab tests or safetyPrater et al., 2024Journal of the Academy of Nutrition and Dietetics · PubMed
No Observed Difference in Inflammatory and Coagulation Markers Following Diets Rich in n-6 Polyunsaturated Fat vs Monounsaturated Fat in Adults With Untreated Hypercholesterolemia: A Randomized Trial.
42 people · adults aged 30 to 75 with high cholesterol or blood fats, not on treatment
TestedMeals with 30% of energy from cottonseed oil (rich in omega-6) vs olive oil, for 8 weeks
No difference between cottonseed oil and olive oil in C-reactive protein (P = 0.70), tumor necrosis factor-α (P = 0.98), interleukin-6 (P = 0.21) or other inflammation and clotting markers.
No differenceNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Effects of n-6 PUFA-rich soybean oil, MUFA-rich olive oil and camellia seed oil on weight and cardiometabolic profiles among Chinese women: a 3-month double-blind randomized controlled-feeding trial.
90 people · middle-aged and older Chinese women at high heart risk
TestedCooking with soybean oil vs olive oil vs camellia seed oil for 3 months
Body weight did not differ between soybean, olive and camellia oil groups. Olive oil raised HDL cholesterol slightly (P = 0.03) vs soybean oil. Authors say the oleic-rich oils looked more favorable.
No differenceNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Randomized trial · lab tests or safetyBjermo et al., 2012The American journal of clinical nutrition · PubMed
Effects of n-6 PUFAs compared with SFAs on liver fat, lipoproteins, and inflammation in abdominal obesity: a randomized controlled trial.
61 people · adults with belly fat, 15% with type 2 diabetes
Tested10 weeks of a diet high in vegetable omega-6 oils vs a diet high in butter fat
Omega-6 diet gave less liver fat than butter diet (16%, MRI; P < 0.001). Inflammation markers TNF receptor-2 (P < 0.01) and IL-1 receptor antagonist (P = 0.02) were lower. No sign of added inflammation.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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The relationship between polyunsaturated fatty acids and inflammation: evidence from cohort and Mendelian randomization analyses.
15,203 people · adults and young people in two UK studies, plus gene data
TestedDietary omega-3 and omega-6 fats and omega-6 to omega-3 ratio, vs blood inflammation markers
In cohorts, total omega-6 was linked to higher GlycA, an inflammation marker (mean difference = 0.52; 95% CI = 0.48, 0.55); omega-3 was too (0.33). A higher omega-6:omega-3 ratio went with higher CRP, GlycA and IL-6. Authors found no simple pro- vs anti-inflammatory split.
MixedNo disclosure in PubMedAbstract onlyNo disclosure in PubMed. Funded by Wellcome Trust and UK Medical Research Council.
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Associations of fats and carbohydrate intake with cardiovascular disease and mortality in 18 countries from five continents (PURE): a prospective cohort study.
135,335 people · adults aged 35 to 70 in 18 countries, followed a median 7.4 years
TestedHighest vs lowest fifth of polyunsaturated fat intake (and other fats and carbs), from food questionnaires
Highest polyunsaturated fat intake went with lower risk of death from any cause (HR 0·80 [0·71-0·89]). Fat types were not linked to heart attack or heart deaths.
MixedNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Health Effects of Various Edible Vegetable Oil: An Umbrella Review.
48 studies · adults in studies of different vegetable oils
TestedEating various vegetable oils such as canola, olive, rice bran, coconut and palm oil, compared across 206 pooled analyses
Canola, olive and rice bran oils lowered total cholesterol and LDL (bad cholesterol). Coconut and palm oil raised them. Evidence was moderate to very low certainty. Heart attacks not reported.
Points to benefitNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Micronutrient Supplementation to Reduce Cardiovascular Risk.
884 studies, 883,627 people · adults in trials of 27 supplements
TestedSupplements such as omega-3, omega-6, vitamins and minerals vs control
Pooled 884 trials with 883,627 people testing 27 supplements. Omega-6 (n-6) fatty acid supplements were among those with moderate- to high-quality evidence for lowering heart risk factors. No separate omega-6 numbers are given.
Points to benefitCompany stakeAbstract onlyOne author got honoraria from Abbott Nutrition and advises other nutrition and health firms.
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Pooled review (meta-analysis)Hooper et al., 2020The Cochrane database of systematic reviews · PubMed
Reduction in saturated fat intake for cardiovascular disease.
15 studies, 59,000 people · adults with and without heart disease
TestedEating less saturated fat for at least 2 years, replaced by polyunsaturated fat, carbohydrate or other, vs usual diet
Pooled 15 trials (~59,000 people). Cutting saturated fat cut combined heart and blood vessel events by 21% (RR 0.79; 95% CI 0.66 to 0.93). Swapping it for polyunsaturated fat or carbohydrate looked equally useful. No separate polyunsaturated fat number.
Points to benefitNo stake declaredAbstract onlyFunded by the World Health Organization; no company ties declared.
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Beneficial effects of linoleic acid on cardiometabolic health: an update.
general adult population
TestedHigher linoleic acid intake and blood levels, reviewed from earlier studies
Review says higher linoleic acid intake and blood levels go with lower risk of heart disease, stroke and type 2 diabetes. It lowers LDL cholesterol compared with saturated fat.
No weight on the ladderCompany stakeAbstract onlyTwo authors co-own OmegaQuant, a fatty acid testing lab; one author got funding from the United Soybean Board.
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Beneficial Outcomes of Omega-6 and Omega-3 Polyunsaturated Fatty Acids on Human Health: An Update for 2021.
general population
TestedLinoleic acid and other omega-6 and omega-3 fats, reviewed from earlier studies
Review says moderate intake of linoleic acid is linked to lower risk of heart disease in long-term cohort studies, likely from lower blood cholesterol. Much of it covers omega-3 fish oil. No numbers given.
No weight on the ladderCompany stakeAbstract onlyOne author advises companies selling fats and oils or supplements, including DSM, BASF and Cargill.
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Opinion or narrative reviewWang, 2018Prostaglandins, leukotrienes, and essential fatty acids · PubMed
Dietary n-6 polyunsaturated fatty acids and cardiovascular disease: Epidemiologic evidence.
general adult population in cohort studies and trials
TestedHigher omega-6 intake, and swapping saturated fat for omega-6, reviewed from earlier studies
Review says long-term cohort studies link higher omega-6 intake to lower heart disease risk, and swapping saturated fat for omega-6 cut risk. No numbers given.
No weight on the ladderNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
41 papers we read and set aside as off topic
- Rodriguez et al., 2022. Update on Omega-3 Polyunsaturated Fatty Acids on Cardiovascular Health. (opinion or narrative review)
- Liao et al., 2019. Efficacy of omega-3 PUFAs in depression: A meta-analysis. (pooled review (meta-analysis))
- Fernández-Lázaro et al., 2024. Omega-3 Fatty Acid Supplementation on Post-Exercise Inflammation, Muscle Damage, Oxidative Response, and Sports Performance in Physically Healthy Adults-A Systematic Review of Randomized Controlled Trials. (systematic review)
- Abdelhamid et al., 2020. Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease. (pooled review (meta-analysis))
- Kavyani et al., 2022. Efficacy of the omega-3 fatty acids supplementation on inflammatory biomarkers: An umbrella meta-analysis. (pooled review (meta-analysis))
- Philippou et al., 2021. Rheumatoid arthritis and dietary interventions: systematic review of clinical trials. (systematic review)
- Liu et al., 2025. Effect of omega-3 polyunsaturated fatty acid on endometriosis. (pooled review (meta-analysis))
- Lok et al., 2026. Fish-Oil Supplementation and Cardiovascular Events in Patients Receiving Hemodialysis. (randomized trial)
- Posnakidis et al., 2024. Effects of Supplementation with Omega-3 and Omega-6 Polyunsaturated Fatty Acids and Antioxidant Vitamins, Combined with High-Intensity Functional Training, on Exercise Performance and Body Composition: A Randomized, Double-Blind, Placebo-Controlled Trial. (randomized trial)
- Konert et al., 2026. Effect of 21-Day Omega-3 Polyunsaturated Fatty Acid Supplementation on Exercise-Induced Secretory Factors and Inflammation Status in Young Men: A Randomized Double-Blind Trial. (randomized trial)
- Ge et al., 2024. Parenteral n-3 polyunsaturated fatty acids supplementation improves postoperative recovery for patients with Crohn's disease after bowel resection: a randomized, unblinded controlled clinical trial. (randomized trial)
- Niseteo et al., 2024. Effect of Omega-3 Polyunsaturated Fatty Acid Supplementation on Clinical Outcome of Atopic Dermatitis in Children. (randomized trial)
- Tindall et al., 2020. Walnuts and Vegetable Oils Containing Oleic Acid Differentially Affect the Gut Microbiota and Associations with Cardiovascular Risk Factors: Follow-up of a Randomized, Controlled, Feeding Trial in Adults at Risk for Cardiovascular Disease. (randomized trial)
- Bunout et al., 2021. A Randomized, Double-Blind, Placebo-Controlled Clinical Trial of an Omega-3 Fatty Acid Supplement in Patients With Predialysis Chronic Kidney Disease. (randomized trial)
- Papandreou et al., 2020. Administration of an Intravenous Fat Emulsion Enriched with Medium-Chain Triglyceride/ω-3 Fatty Acids is Beneficial Towards Anti-Inflammatory Related Fatty Acid Profile in Preterm Neonates: A Randomized, Double-Blind Clinical Trial. (randomized trial)
- Kyriakidou et al., 2021. The effect of Omega-3 polyunsaturated fatty acid supplementation on exercise-induced muscle damage. (randomized trial)
- Einvik et al., 2010. A randomized clinical trial on n-3 polyunsaturated fatty acids supplementation and all-cause mortality in elderly men at high cardiovascular risk. (randomized trial)
- Haghiac et al., 2015. Dietary Omega-3 Fatty Acid Supplementation Reduces Inflammation in Obese Pregnant Women: A Randomized Double-Blind Controlled Clinical Trial. (randomized trial)
- Rozanova et al., 1997. [Effect of antiatherosclerotic diet, containing polyunsaturated fatty acids of the omega-3 family from flax oil, on fatty acid composition of cell membranes of patients with ischemic heart disease. Hypertensive disease and hyperlipoproteinemia]. (trial, not randomized)
- Kristensen et al., 2018. Beneficial effect of n-3 polyunsaturated fatty acids on inflammation and analgesic use in psoriatic arthritis: a randomized, double blind, placebo-controlled trial. (randomized trial)
- de Luis et al., 2011. Double blind randomized clinical trial controlled by placebo with an alpha linoleic acid and prebiotic enriched cookie on risk cardiovascular factor in obese patients. (randomized trial)
- Brignole-Baudouin et al., 2011. A multicentre, double-masked, randomized, controlled trial assessing the effect of oral supplementation of omega-3 and omega-6 fatty acids on a conjunctival inflammatory marker in dry eye patients. (randomized trial)
- Jannas-Vela et al., 2023. Role of specialized pro-resolving mediators on inflammation, cardiometabolic health, disease progression, and quality of life after omega-3 PUFA supplementation and aerobic exercise training in individuals with rheumatoid arthritis: a randomized 16-week, placebo-controlled interventional trial. (trial plan, no results yet)
- Thusgaard et al., 2009. Effect of fish oil (n-3 polyunsaturated fatty acids) on plasma lipids, lipoproteins and inflammatory markers in HIV-infected patients treated with antiretroviral therapy: a randomized, double-blind, placebo-controlled study. (randomized trial)
- Djuricic et al., 2023. Pros and Cons of Long-Chain Omega-3 Polyunsaturated Fatty Acids in Cardiovascular Health. (opinion or narrative review)
- Simopoulos, 2016. An Increase in the Omega-6/Omega-3 Fatty Acid Ratio Increases the Risk for Obesity. (opinion or narrative review)
- Haycock et al., 2023. The association between genetically elevated polyunsaturated fatty acids and risk of cancer. (gene study (mendelian randomization))
- Román et al., 2019. Mediterranean diet: The role of long-chain ω-3 fatty acids in fish; polyphenols in fruits, vegetables, cereals, coffee, tea, cacao and wine; probiotics and vitamins in prevention of stroke, age-related cognitive decline, and Alzheimer disease. (opinion or narrative review)
- Mozaffarian et al., 2011. Omega-3 fatty acids and cardiovascular disease: effects on risk factors, molecular pathways, and clinical events. (opinion or narrative review)
- Innes et al., 2020. Marine Omega-3 (N-3) Fatty Acids for Cardiovascular Health: An Update for 2020. (opinion or narrative review)
- Watanabe et al., 2017. Omega-3 polyunsaturated fatty acids for cardiovascular diseases: present, past and future. (opinion or narrative review)
- Augimeri et al., 2021. Nutraceuticals in the Mediterranean Diet: Potential Avenues for Breast Cancer Treatment. (opinion or narrative review)
- Schwärzler et al., 2022. PUFA-Induced Metabolic Enteritis as a Fuel for Crohn's Disease. (other)
- Tian et al., 2025. No causal relationship between polyunsaturated fatty acids and inflammatory bowel disease: A Mendelian randomization study. (gene study (mendelian randomization))
- Kim et al., 2025. Causal association between polyunsaturated fatty acids and acne: a two-sample Mendelian randomization study. (gene study (mendelian randomization))
- Ros et al., 2021. Nuts: Natural Pleiotropic Nutraceuticals. (opinion or narrative review)
- Zhou et al., 2024. Unraveling the causal link: fatty acids and inflammatory bowel disease. (gene study (mendelian randomization))
- Okuyama et al., 2018. A Critical Review of the Consensus Statement from the European Atherosclerosis Society Consensus Panel 2017. (opinion or narrative review)
- Chrysant et al., 2024. Olive Oil Consumption and Cardiovascular Protection: Mechanism of Action. (opinion or narrative review)
- Lakshimi et al., 2023. New Insights into Prospective Health Potential of ω-3 PUFAs. (opinion or narrative review)
- Lin et al., 2022. Omega-3 Fatty Acids Improve Chronic Kidney Disease-Associated Pruritus and Inflammation. (population study: followed a group)
Words on this page
- Hazard ratio (HR)
- Compares how often something happened in two groups over time. 1 means no difference. 0.80 means 20% lower risk; 1.20 means 20% higher.
- Relative risk (RR)
- Compares the risk in two groups. 1 means no difference. 0.85 means 15% lower risk.
- 95% CI (confidence interval)
- The range where the true result likely lies. If the range includes no effect (1 for ratios, 0 for differences), the result is not clear.
- p-value (p =)
- How likely a result this large would be by chance if there were no real effect. Below 0.05 is usually called a clear result.
- Pooled review (meta-analysis)
- A study that combines the results of many earlier studies to get one overall answer.
- Umbrella review
- A review of many pooled reviews.
- Cohort study
- A study that follows a large group of people over years. It shows links, not causes.
- Marker
- A lab or scan result that stands in for a health outcome. A better marker does not always mean better health.
How the short answer is set
Fixed rules turn the studies into the short answer, so the same studies always give the same answer. The rules start from GRADE, a standard system for rating evidence, in plain language.
| Confidence | What it means |
|---|---|
| High | We are confident the answer is right. |
| Moderate | The answer is probably right, but it could change. |
| Low | The answer may well change. |
| Very low (this page) | Any answer is very uncertain. |
| Not tested in people | Only cell or animal studies exist. |
Why very low here
- Heart-event trials exist, but the linoleic acid trial dates from 1966-73.
- Results conflict: one trial found more deaths; pooled trials and cohorts did not.
- Most trials measured only markers, like cholesterol or inflammation, for weeks.
- Key ranges are wide; the pooled linoleic acid result included no effect.
Hard limit used. The heart-event evidence comes from one 1966-73 trial and from pooled trials that do not separate seed oils from other polyunsaturated fats, so no firm answer is possible.
How this page was made
Label
- Search
- PubMed, Nov 14, 2026. Searches written by Claude Opus 5.5; papers ranked by PubMed
- First read of all 54 papers
- Claude Sonnet
- Independent second read
- Claude Haiku
- Disagreements settled by
- Claude Opus 5.5
- Page text written by
- Claude Opus 5.5
- Charts
- Drawn by code from the study records
- Source check by a person
- Not yet. Required before search engines may list this page.
- Expert review
- No
- Papers read in full
- 0 of 54; all from PubMed abstracts
- Method
- v0.2, created Nov 14, 2026
Search. We ran four PubMed searches for seed oils and linoleic acid and heart disease and inflammation: pooled and systematic reviews since 2012 (10 of 355), trials in people (22 of 1,110), population studies (22 of 1,115). The first number is how many papers we read; the second is how many PubMed found. We took the ones PubMed ranks as most relevant. See the full PubMed search. Of the 54 papers read, 13 were on topic.
Limits. Digestery reads at most about 60 papers per question, so large fields are sampled, not covered in full. Abstracts can leave out key details, such as side effects and funding.
Review queue
These items wait for a person. Search engines are asked not to list the page until the first one is done.
- OpenThe short answer is new. It waits for a source check by a person.
- OpenPapandreou 2020 (soybean oil fat drip in preterm newborns, IL-6) kept off-topic as not a close form of eating seed oils; please confirm.
- OpenHooper 2020 (Cochrane saturated fat) added as relevant and Dehghan 2017 (PURE) kept, though both cover all polyunsaturated fat, not seed oils; confirm inclusion.
- OpenLakshimi 2023 and Okuyama 2018 are off-topic reviews asserting omega-6 or vegetable oils drive heart disease, with no data; decide whether the page should mention them.
- OpenLok 2026, Einvik 2010 and Bunout 2021 used corn oil as placebo in fish oil trials; kept off-topic because they test fish oil.
- OpenFour of five trial papers (Prater 2024, Wu 2022, She 2026, Bjermo 2012) have no COI statement in PubMed; check full texts for disclosures.
- OpenThe updated linoleic acid meta-analysis in Ramsden 2013 may share trials with Cochrane Hooper 2020; abstracts do not list included trials.
- OpenAn 2022 rests on one line about n-6 supplements with no number; check the full text for the omega-6 estimate and trial count.
- OpenRozanova 1997 (flax oil) kept off-topic: its abstract describes flax as an omega-3 source, not a linoleic acid-rich oil.
Page history
| Date | Change | Reason |
|---|---|---|
| Nov 14, 2026 | Page created from 54 papers. | First version of the page. |
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