Sunflower oil is not one product. The traditional pressing is dominated by an omega-6 fat and carries more vitamin E than any other common cooking oil; the newer high-oleic version, bred closer to olive oil, is far more stable in a hot pan. Replacing butter or lard lowers cholesterol; repeated high-temperature frying carries most of the documented harm. (Full Review)
| Marker | Target | Why |
|---|---|---|
| LDL Cholesterol | < 2.6 mmol/L (100 mg/dL) | The outcome the substitution effect acts on |
| Apolipoprotein B | < 0.8 g/L | Counts every artery-entering particle, not just their cholesterol load |
| Lipoprotein(a) | < 30 nmol/L | Largely genetic and diet-resistant; sunflower oil lowers it modestly |
| Omega-3 Index | ≥ 8% | The buffer against membrane displacement by omega-6 fat |
| Red Cell or Plasma Linoleic Acid | 25–32% of total fatty acids | Direct exposure marker; tracks intake over months, not days |
| Serum α-Tocopherol | 20–35 µmol/L | Confirms the antioxidant buffer matches the polyunsaturated load |
| High-Sensitivity C-Reactive Protein | < 1.0 mg/L | The inflammatory endpoint the omega-6 debate turns on |
| Alanine Aminotransferase and Gamma-Glutamyl Transferase | ALT < 25 U/L (men), < 20 U/L (women); GGT < 25 U/L | Liver fat is where the saturated-versus-polyunsaturated difference shows first |
| Fasting Glucose and Insulin | Glucose 4.4–5.0 mmol/L; insulin < 36 pmol/L | Feeds the insulin resistance calculation tracked in the diabetes evidence |
| Oxidised LDL | No established target range; track change from the individual's own baseline | The mechanistic endpoint claimed by the oxidation hypothesis |
Cadence: Baseline draw before starting or removing the oil; lipids and apolipoprotein B rechecked at six to eight weeks, then annually; omega-3 index, α-tocopherol, inflammatory and liver markers at six months, then every six to twelve months, or sooner after any substantial change in cooking fat, frying frequency or omega-3 intake