Across 3 studies, 2 report beneficial effects (one moderate, one small) and 1 neutral effect. The only statistically significant finding comes from a review citing large-scale trials (PREDIMED, Seven Countries Study). Predominant effect size appears mixed (small to moderate) due to conflicting systematic review results. No dose range or population can be determined from available data.
Caveats: Evidence base is small (only 3 studies) — conclusions are preliminary. One systematic review (2024) showed conflicting results for cardiovascular outcomes, tempering the positive signal from other reviews. Many studies in this area are narrative reviews, not RCTs. Publication bias is possible given the overwhelmingly positive clinical literature on olive oil, though not confirmed here due to small study count.
showed conflicting results for cardiovascular outcomes
generally report improvements in blood pressure, vascular function, lipid profiles, and inflammatory markers
Studies such as PREDIMED and the Seven Countries Study have demonstrated its role in preventing cardiovascular events and reducing blood pressure.