The claimEvidence B · meta-analysis
Seed oils (omega-6) are toxic, inflammatory, fattening
The evidence
Lacks human evidence. PUFA replacing saturated fat lowers CHD (Mozaffarian 2010); the appetite hypothesis is mouse-only (Alvheim 2012). The real issue is the 'fried + packaged' food form, not the molecule.
The mechanism, in brief
Start with cardiovascular disease — the area with the most evidence in the omega-6 debate, and the conclusion may not fully match either camp.
Sources (2)
- Mozaffarian, D., Micha, R., & Wallace, S. (2010). Effects on coronary heart disease of increasing polyunsaturated fat in place of saturated fat: a systematic review and meta-analysis of randomized controlled trials. PLoS Medicine, 7(3), e1000252. Replacing saturated fat with polyunsaturated fat reduced CHD events ~19% (RR 0.81, 95% CI 0.70-0.95), ~10% per 5% energy.
- Hooper, L., Al-Khudairy, L., Abdelhamid, A. S., Rees, K., Brainard, J. S., Brown, T. J., et al. (2018). Omega-6 fats for the primary and secondary prevention of cardiovascular disease. Cochrane Database of Systematic Reviews, (11), CD011094. Increasing omega-6 fats made little or no difference to cardiovascular events or mortality (low-certainty evidence), with a possible small reduction in myocardial infarction.