From American Family Physician:
“Cardiovascular disease (CVD) is the leading cause of death in the United States. One-third of these deaths may be preventable through healthy lifestyle choices including diet and physical activity. The Mediterranean diet is associated with reduced cardiovascular mortality [deaths], whereas the Dietary Approaches to Stop Hypertension (DASH) eating plan is associated with a reduced risk of coronary artery disease.”
Source: Diet and Physical Activity for Cardiovascular Disease Prevention – American Family Physician
There are at least a couple versions of the DASH diet. The most common one is low in total and saturated fats and cholesterol, moderate in low-fat dairy products, high in fruits and vegetables, low in salt, low in sweetened beverages, moderate in whole grains, and low in animal protein but has substantial amounts of plant protein from nuts and legumes.
The Mediterranean diet also has several versions. My favorite ones are here:
Two diet books in one
Advanced Mediterranean Diet 