Analysis of 14 randomized trials involving 14,065 cardiovascular disease patients found Mediterranean diet interventions reduced CVD mortality by 60% (relative risk 0.40). Observational data from 104,386 patients showed even stronger protective effects: 29% reduction in all-cause mortality, 25% lower CVD mortality, and 17% decreased cardiovascular event recurrence with high Mediterranean diet adherence. This represents one of the most compelling dietary intervention findings for secondary prevention, where patients already have established heart disease. The Mediterranean pattern's anti-inflammatory omega-3 fatty acids, polyphenol-rich olive oil, and fiber from vegetables likely work synergistically to stabilize atherosclerotic plaques and improve endothelial function. However, the evidence has notable limitations. High heterogeneity between studies (up to 76%) and methodological concerns in 65% of trials weaken confidence in these dramatic effect sizes. Most compelling is the dose-response relationship seen across both controlled trials and observational studies, suggesting genuine biological effects rather than statistical artifacts. For practicing physicians, this provides robust justification for prioritizing Mediterranean dietary counseling in post-cardiac event patients, though standardized protocols remain needed.