Olive Oil

What this is

Olive oil covers several edible grades. Extra virgin and virgin oils are obtained by physical methods, while ordinary olive oil can blend refined and virgin oil; olive-pomace oil is a separate category. Refining and cultivar affect minor compounds, so benefits studied with extra virgin oil cannot automatically be assigned to every grade. Large Mediterranean-diet trials reduced cardiovascular events, but changed whole eating patterns and did not isolate olive oil. Cohort studies associate replacing butter with olive oil with lower mortality, without proving causation. A small crossover trial found no overall LDL difference between higher and lower extra virgin oil intake within a plant-based diet. In 2025, EFSA found insufficient evidence for a separate claim that olive phenolics lower LDL cholesterol or systolic blood pressure. New mouse studies report fat-cell, glucose-control, and implanted-tumor metastasis signals under high-fat conditions; they do not establish those outcomes in people eating ordinary amounts. A small eight-week trial in healthy women found no blood-pressure difference from sunflower oil and mixed other markers; an LDL rise within the olive group does not establish comparative harm. Repeated heating depletes phenolics, and refined grades require contaminant controls.

Safety Review

The health areas reviewed when evaluating an ingredient. This does not mean the ingredient is proven to cause harm.

Human cardiovascular findings mainly concern Mediterranean eating patterns or replacing other fats, and do not show that adding unlimited olive oil prevents disease or that every grade provides the same benefit. Recent mouse experiments found increased fat-cell formation, impaired glucose control, or greater lung metastasis after implanted breast tumors under different high-fat conditions; these are material experimental signals, but they do not establish human obesity, diabetes, or cancer causation from ordinary olive-oil intake. Repeated frying can substantially reduce phenolics, and contaminants formed during refining require exposure controls, with stricter limits for oils intended for infant foods. The overall concern remains low for ordinary food use, with uncertainty about long-term isolated-oil effects and actual restaurant processing conditions.