If seed oils are healthy, then why... …do animal studies show higher cancer incidence with high-PUFA diets compared to saturated-fat diets? …do cultures eating traditional low-PUFA diets (e.g., pre-industrial Japan, Mediterranean regions before refined oils) have far lower rates of obesity, diabetes, and cardiovascular disease than populations high in seed oils? …does linoleic acid oxidize into toxic aldehydes (like 4-HNE, MDA) at body temperature, which are implicated in atherosclerosis and neurodegeneration? …do oxidized linoleic acid metabolites (OXLAMs) accumulate in human plasma and are linked to cardiovascular disease? …do rats fed high-PUFA diets show increased mitochondrial dysfunction and oxidative stress compared to saturated-fat diets? …does heating seed oils during frying produce mutagenic and cytotoxic aldehydes at levels found in restaurant food? …do high omega-6 : omega-3 ratios correlate with higher risk of depression, obesity, and inflammation? …did re-analyses of older RCTs (Sydney Diet Heart Study, Minnesota Coronary Experiment) show that replacing saturated fat with seed oils lowered cholesterol but increased mortality? …do people with high tissue linoleic acid levels show higher susceptibility to lipid peroxidation and oxidative damage? …do polyunsaturated fats make cell membranes more fragile and prone to free radical attack compared to monounsaturated or saturated fats? …do cooking and refining remove antioxidants (vitamin E, polyphenols), leaving oils more vulnerable to oxidation? …do fried foods cooked in seed oils correlate with increased cardiovascular mortality in large cohorts? …do endogenous antioxidants (glutathione, SOD, catalase) get depleted under high-PUFA diets, increasing oxidative stress burden? …does high linoleic acid intake worsen alcoholic liver injury in humans and animals? …do patients with Alzheimer’s disease show higher levels of lipid peroxidation products derived from linoleic acid?