“Seed oils are toxic”

## The Claim and Its Proponents The seed oil concern centres on: (1) high omega-6 content disrupting omega-6:omega-3 ratios, (2) oxidation of polyunsaturated fats during high-heat cooking producing aldehydes, and (3) linoleic acid driving inflammation. These concerns are raised by figures like Paul Saladino and Tucker Goodrich. ## What the Evidence Shows A 2020 meta-analysis in *Circulation* (Sacks et al., plus the pooled Cochrane analysis by Hooper et al.) found replacing saturated fat with polyunsaturated fat (primarily linoleic acid from seed oils) reduces cardiovascular events by 17–30%. Randomised trial evidence consistently supports PUFA over SFA for heart health. Regarding oxidation: Yes, heating seed oils to smoking point produces aldehydes. However, (1) this is true of many fats at excessive heat, and (2) circulating linoleic acid in humans does not undergo the same oxidation kinetics as heated oil in a pan. The omega-6:omega-3 ratio hypothesis is biologically plausible but lacks human trial evidence. Populations with high olive oil consumption (Mediterranean diet, well-evidenced for longevity) also consume substantial omega-6. ## The Nuance Minimally processed seed oils (cold-pressed, used at appropriate temperatures) are not equivalent to repeatedly reheated industrial frying oil. Ultra-processed foods (which happen to contain seed oils) are clearly harmful — but the seed oils may not be the causal agent.